Add $pic_flag to archive_cmds and archive_expsym_cmds.

Add $pic_flag to archive_cmds and archive_expsym_cmds.

* libltdl/m4/libtool.m4 (_LT_LINKER_SHLIBS)
<archive_cmds, archive_expsym_cmds>
[GNU ld, netbsd]: Add $pic_flag if ELF.
[GNU ld, solaris]: Likewise.
[GNU ld, default case]: Likewise.
[!GNU ld, freebsd, dragonfly]: Add $pic_flag.
[!GNU ld, GCC, hpux9]: Add $pic_flag.
[!GNU ld, GCC, hpux10]: Replace -fPIC with $pic_flag
[!GNU ld, GCC, hpux11, !hppa*64]: Replace -fPIC with $pic_flag.
[!GNU ld, GCC, irix5, irix6, nonstopux]: Add $pic_flag.
[!GNU ld, GCC, osf4, osf5]: Likewise.
[!GNU ld, GCC, solaris]: Likewise.
(_LT_LANG_CXX_CONFIG) <archive_cmds, archive_expsym_cmds>
[hpux9]: Add $pic_flag if $GXX.
[hpux10, hpux11, !hppa*64]: Replace -fPIC with $pic_flag.
[irix5, irix6]: Add $pic_flag if $GXX.
[osf4, osf5]: Likewise.
[solaris]: Add $pic_flag if $GXX and not GCC 2.7.

Signed-off-by: Ralf Wildenhues <Ralf.Wildenhues@gmx.de>