re PR go/91617 (Many go test case failures after r275026)

re PR go/91617 (Many go test case failures after r275026)

	PR go/91617
	* fold-const.c (range_check_type): For enumeral and boolean
	type, pass 1 to type_for_size langhook instead of
	TYPE_UNSIGNED (etype).  Return unsigned_type_for result whenever
	etype isn't TYPE_UNSIGNED INTEGER_TYPE.
	(build_range_check): Don't call unsigned_type_for for pointer types.
	* match.pd (X / C1 op C2): Don't call unsigned_type_for on
	range_check_type result.

From-SVN: r275299