dwarf.c (find_address_ranges): New static function, broken out of build_address_map.

	* dwarf.c (find_address_ranges): New static function, broken out
	of build_address_map.
	(build_address_map): Call it.
	* btest.c (check): Check for missing filename or function, rather
	than crashing.
	(f3): Check that enough frames were returned.

From-SVN: r205490