re PR bootstrap/51725 (segfault in stage 3 when compiling gcc/opts.c for sparc64-linux)

	PR bootstrap/51725
	* cselib.c (new_elt_loc_list): When moving locs from one
	cselib_val to its new canonical_cselib_val and the
	cselib_val was in first_containing_mem chain, but
	the canonical_cselib_val was not, add the latter into the
	chain.
	(cselib_invalidate_mem): Compare canonical_cselib_val of
	addr_list chain elt with v.

From-SVN: r182858