cobol, driver, libgcobol: Add support for libgcobol.spec.

cobol, driver, libgcobol: Add support for libgcobol.spec.

Ads support for using a library spec file (e.g. to include the
target requirements for non-standard libraries - or even libm
which we can now configure at the target side).

gcc/cobol/ChangeLog:

	* gcobolspec.cc (SPEC_FILE): New.
	(lang_specific_driver): Make the 'need libgcobol' flag global
	so that the prelink callback can use it. Libm use is now handled
	via the library spec.
	(lang_specific_pre_link): Include libgcobol.spec where needed.

libgcobol/ChangeLog:

	* Makefile.am: Add libgcobol.spec and dependency.
	* Makefile.in: Regenerate.
	* configure: Regenerate.
	* configure.ac: Add libgcobol.spec handling.
	* libgcobol.spec.in: New file.

Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>