PR libfortran/33583
	PR libfortran/33698

	* intrinsics/c99_functions.c (tgamma, tgammaf, lgamma, lgammaf):
	New fallback functions.
	* c99_protos.h (tgamma, tgammaf, lgamma, lgammaf): New prototypes.
	* configure.ac: Add checks for tgamma, tgammaf, tgammal, lgamma,
	lgammaf and lgammal.
	* config.h.in: Regenerate.
	* configure: Regenerate.

From-SVN: r130245