Re: ld/testsuite: adjust ld-arm to run shared tests only when supported

commit 67527cffcd enabled previously disabled tests unresolved-1-dyn,
thumb-plt and thumb-plt-got for nacl.  The first fails due to trying
to link against mixed-lib.so which isn't compiled for nacl.  The last
two fail with
objdump: tmpdir/dump(.rel.plt): relocation 0 has invalid symbol index 14885104
and
readelf: Error:  bad symbol index: 00e320f0 in reloc

Relocation section '.rel.plt' at offset 0x128 contains 1 entry:
 Offset     Info    Type                Sym. Value  Symbol's Name
e320f000  e320f000 R_ARM_NONE

	* testsuite/ld-arm/arm-elf.exp: Disable unresolved-1-dyn,
	thumb-plt and thumb-plt-got for nacl.
diff --git a/ld/testsuite/ld-arm/arm-elf.exp b/ld/testsuite/ld-arm/arm-elf.exp
index 5a3df83..e53b9bb 100644
--- a/ld/testsuite/ld-arm/arm-elf.exp
+++ b/ld/testsuite/ld-arm/arm-elf.exp
@@ -1247,7 +1247,7 @@
 run_dump_test "attr-merge-hardfp-use-1"
 run_dump_test "attr-merge-hardfp-use-2"
 run_dump_test "unresolved-1"
-if { [check_shared_lib_support] } {
+if { !$is_nacl && [check_shared_lib_support] } {
     run_dump_test "unresolved-1-dyn"
 }
 run_dump_test "unresolved-2"
@@ -1272,7 +1272,7 @@
 run_dump_test "non-contiguous-arm5"
 run_dump_test "non-contiguous-arm6"
 
-if { [check_shared_lib_support] } {
+if { !$is_nacl && [check_shared_lib_support] } {
     run_dump_test "thumb-plt"
     run_dump_test "thumb-plt-got"
 }