lto: Remove stream_input_location_now

lto: Remove stream_input_location_now

As discussed yesterday, stream_input_location_now has been used in 3
remaining places.  For ERT_MUST_NOT_THROW, I believe the failure_loc
location is stable at least until the apply_cache after the bbs are all
read, and the locations do not include BLOCK, so we can use normal
stream_input_location, and the two input_struct_function_base also
shouldn't include BLOCK and are stable at least until that same apply_cache
after reading all bbs, so again we can use the location cache.

2020-09-04  Jakub Jelinek  <jakub@redhat.com>

	* lto-streamer.h (stream_input_location_now): Remove declaration.
	* lto-streamer-in.c (stream_input_location_now): Remove.
	(input_eh_region, input_struct_function_base): Use
	stream_input_location instead of stream_input_location_now.