Was triggered by defined(__sparcv9) so only built on Solaris SPARC 64-bit.
Inconsistent with all other platforms, and a bit overcomplicated.

Should anyone need to continue using that path, simply build with
a #define POSTLOCALELIBDIR "sparcv9" to get the same result.

Fixes Solaris bug 7038737:
 sparcv9 Xlib looking in wrong path for i18n loadable modules
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Daniel Stone <daniel@fooishbar.org>
Backported-to-NX-by: Ulrich Sibiller <uli42@gmx.de>