Canonicalize canonical type hashing

Canonicalize canonical type hashing

	Canonicalize canonical type hashing
	gcc/
	* tree.h (type_hash_canon_hash): Declare.
	* tree.c (type_hash_list, attribute_hash_list): Move into
	type_hash_canon_hash.
	(build_type_attribute_qual_variant): Break out hash code calc into
	type_hash_canon_hash.
	(type_hash_canon_hash): New.  Generic type hash computation.
	(build_range_type_1, build_array_type_1, build_function_type)
	build_method_type_directly, build_offset_type, build_complex_type,
	make_vector_type): Call it.
	gcc/c-family/
	* c-common.c (complete_array_type): Use type_hash_canon.
(--This line, and those below, will be ignored--

M    gcc/tree.c
M    gcc/tree.h
M    gcc/c-family/ChangeLog
M    gcc/c-family/c-common.c
M    gcc/ChangeLog

From-SVN: r247546