libtool: Change how version is derived

Avoid duplication of '(GNU @PACKAGE@) @VERSION@' in multiple
places by using '$scriptversion'.

* libtoolize.in, build-aux/ltmain.in: Change version from
  '(GNU @PACKAGE@) @VERSION@' to '$scriptversion'.

build-aux/ltmain.in

diff --git a/build-aux/ltmain.in b/build-aux/ltmain.in
index 816b1ca..c5bdbe5 100644
--- a/build-aux/ltmain.in
+++ b/build-aux/ltmain.in
@@ -179,7 +179,7 @@
        compiler:       $LTCC
        compiler flags: $LTCFLAGS
        linker:         $LD (gnu? $with_gnu_ld)
-       version:        $progname (GNU @PACKAGE@) @VERSION@
+       version:        $progname $scriptversion
        automake:       `($AUTOMAKE --version) 2>/dev/null |$SED 1q`
        autoconf:       `($AUTOCONF --version) 2>/dev/null |$SED 1q`
 

libtoolize.in

diff --git a/libtoolize.in b/libtoolize.in
index 5940cc1..6c15aa5 100644
--- a/libtoolize.in
+++ b/libtoolize.in
@@ -140,7 +140,7 @@
 include the following information:
 
        host-triplet:   @host_triplet@
-       version:        $progname (GNU @PACKAGE@) @VERSION@
+       version:        $progname $scriptversion
        automake:       `($AUTOMAKE --version) 2>/dev/null |$SED 1q`
        autoconf:       `($AUTOCONF --version) 2>/dev/null |$SED 1q`