sim: assume sys/select.h always exists

Now that gnulib provides this, assume it exists.
diff --git a/sim/ChangeLog b/sim/ChangeLog
index 54f2216..b90b13a 100644
--- a/sim/ChangeLog
+++ b/sim/ChangeLog
@@ -1,5 +1,10 @@
 2021-06-12  Mike Frysinger  <vapier@gentoo.org>
 
+	* m4/sim_ac_platform.m4: Delete sys/select.h.
+	* config.h.in, configure: Regenerate.
+
+2021-06-12  Mike Frysinger  <vapier@gentoo.org>
+
 	* configure.ac: Call SIM_AC_OPTION_ALIGNMENT.
 	* m4/sim_ac_option_alignment.m4: Delete wire and default alignment.
 	* aclocal.m4, config.h.in, configure, Makefile.in: Regenerate.
diff --git a/sim/common/ChangeLog b/sim/common/ChangeLog
index ff0f4e2..19e93bb 100644
--- a/sim/common/ChangeLog
+++ b/sim/common/ChangeLog
@@ -1,5 +1,9 @@
 2021-06-12  Mike Frysinger  <vapier@gentoo.org>
 
+	* dv-sockser.c: Include sys/select.h.
+
+2021-06-12  Mike Frysinger  <vapier@gentoo.org>
+
 	* Make-common.in: Delete SIM_ALIGNMENT.
 	* sim-config.c (sim_config): Change WITH_DEFAULT_ALIGNMENT to
 	NONSTRICT_ALIGNMENT.
diff --git a/sim/common/dv-sockser.c b/sim/common/dv-sockser.c
index ef652f6..7f1cf79 100644
--- a/sim/common/dv-sockser.c
+++ b/sim/common/dv-sockser.c
@@ -39,6 +39,7 @@
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <netdb.h>
+#include <sys/select.h>
 #include <sys/socket.h>
 
 #ifndef __CYGWIN32__
diff --git a/sim/config.h.in b/sim/config.h.in
index a1d4f78..6e87686 100644
--- a/sim/config.h.in
+++ b/sim/config.h.in
@@ -287,9 +287,6 @@
 /* Define to 1 if you have the <sys/resource.h> header file. */
 #undef HAVE_SYS_RESOURCE_H
 
-/* Define to 1 if you have the <sys/select.h> header file. */
-#undef HAVE_SYS_SELECT_H
-
 /* Define to 1 if you have the <sys/socket.h> header file. */
 #undef HAVE_SYS_SOCKET_H
 
diff --git a/sim/configure b/sim/configure
index bb3c54c..2d4204f 100755
--- a/sim/configure
+++ b/sim/configure
@@ -2355,7 +2355,6 @@
 as_fn_append ac_header_list " sys/mount.h"
 as_fn_append ac_header_list " sys/param.h"
 as_fn_append ac_header_list " sys/resource.h"
-as_fn_append ac_header_list " sys/select.h"
 as_fn_append ac_header_list " sys/socket.h"
 as_fn_append ac_header_list " sys/stat.h"
 as_fn_append ac_header_list " sys/statfs.h"
@@ -4660,8 +4659,6 @@
 
 
 
-
-
   for ac_func in $ac_func_list
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
diff --git a/sim/cris/ChangeLog b/sim/cris/ChangeLog
index bde34bb..2f4be8d 100644
--- a/sim/cris/ChangeLog
+++ b/sim/cris/ChangeLog
@@ -1,5 +1,10 @@
 2021-06-12  Mike Frysinger  <vapier@gentoo.org>
 
+	* dv-rv.c: Delete HAVE_SYS_SELECT_H.
+	* rvdummy.c: Likewise.
+
+2021-06-12  Mike Frysinger  <vapier@gentoo.org>
+
 	* configure.ac: Delete call to SIM_AC_OPTION_ALIGNMENT.
 
 2021-06-12  Mike Frysinger  <vapier@gentoo.org>
diff --git a/sim/cris/dv-rv.c b/sim/cris/dv-rv.c
index 310155c..89d6408 100644
--- a/sim/cris/dv-rv.c
+++ b/sim/cris/dv-rv.c
@@ -39,9 +39,7 @@
 
 #include <sys/time.h>
 
-#ifdef HAVE_SYS_SELECT_H
 #include <sys/select.h>
-#endif
 
 /* Not guarded in dv-sockser.c, so why here.  */
 #include <netinet/in.h>
diff --git a/sim/cris/rvdummy.c b/sim/cris/rvdummy.c
index b53e823..719b2fc 100644
--- a/sim/cris/rvdummy.c
+++ b/sim/cris/rvdummy.c
@@ -48,16 +48,13 @@
 
 #include <sys/time.h>
 
-#ifdef HAVE_SYS_SELECT_H
-#include <sys/select.h>
-#endif
-
 #include <errno.h>
 
 /* Not guarded in dv-sockser.c, so why here.  */
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <netdb.h>
+#include <sys/select.h>
 #include <sys/socket.h>
 
 enum rv_command {
diff --git a/sim/lm32/ChangeLog b/sim/lm32/ChangeLog
index 3223d90..d47e165 100644
--- a/sim/lm32/ChangeLog
+++ b/sim/lm32/ChangeLog
@@ -1,5 +1,9 @@
 2021-06-12  Mike Frysinger  <vapier@gentoo.org>
 
+	* dv-lm32uart.c: Include sys/select.h.
+
+2021-06-12  Mike Frysinger  <vapier@gentoo.org>
+
 	* configure.ac: Delete call to SIM_AC_OPTION_ALIGNMENT.
 	* sim-if.c (sim_open): Set current_alignment.
 
diff --git a/sim/lm32/dv-lm32uart.c b/sim/lm32/dv-lm32uart.c
index 1f8ba1d..68f02a3 100644
--- a/sim/lm32/dv-lm32uart.c
+++ b/sim/lm32/dv-lm32uart.c
@@ -26,6 +26,7 @@
 #include "sim-assert.h"
 
 #include <stdio.h>
+#include <sys/select.h>
 #include <sys/time.h>
 
 struct lm32uart
diff --git a/sim/m32c/ChangeLog b/sim/m32c/ChangeLog
index 270b590..8d3e606 100644
--- a/sim/m32c/ChangeLog
+++ b/sim/m32c/ChangeLog
@@ -1,5 +1,9 @@
 2021-06-12  Mike Frysinger  <vapier@gentoo.org>
 
+	* mem.c: Delete HAVE_SYS_SELECT_H.
+
+2021-06-12  Mike Frysinger  <vapier@gentoo.org>
+
 	* aclocal.m4, config.in, configure: Regenerate.
 
 2021-06-12  Mike Frysinger  <vapier@gentoo.org>
diff --git a/sim/m32c/mem.c b/sim/m32c/mem.c
index 243b7c4..bc293aa 100644
--- a/sim/m32c/mem.c
+++ b/sim/m32c/mem.c
@@ -29,9 +29,7 @@
 #include <sys/time.h>
 #include <sys/types.h>
 #include <unistd.h>
-#ifdef HAVE_SYS_SELECT_H
 #include <sys/select.h>
-#endif
 #ifdef HAVE_TERMIOS_H
 #include <termios.h>
 #endif
diff --git a/sim/m4/sim_ac_platform.m4 b/sim/m4/sim_ac_platform.m4
index 95760a6..c505c74 100644
--- a/sim/m4/sim_ac_platform.m4
+++ b/sim/m4/sim_ac_platform.m4
@@ -36,7 +36,6 @@
   sys/mount.h
   sys/param.h
   sys/resource.h
-  sys/select.h
   sys/socket.h
   sys/stat.h
   sys/statfs.h