PR libobjc/30445
	* configure.ac (extra_ldflags_libobjc): Define appropriately for
	Cygwin and MinGW hosts.
	* Makefile.am (libobjc_s.a): Remove dead pre-libtool target.
	(libobjc.dll): Likewise.
	* configure: Regenerate.

From-SVN: r157662