gcc.c (LINK_SSP_SPEC): Handle -fstack-protector-explicit for !TARGET_LIBC_PROVIDES_SSP version and...

	* gcc.c (LINK_SSP_SPEC): Handle -fstack-protector-explicit
	for !TARGET_LIBC_PROVIDES_SSP version and
	-fstack-protector-{all,strong,explicit} otherwise.
	* config/freebsd.h (LINK_SSP_SPEC): Handle
	-fstack-protector-{strong,explicit}.

Co-Authored-By: Jakub Jelinek <jakub@redhat.com>

From-SVN: r220014