Replace ssa_range_in_bb with entry exit and def range

Replace ssa_range_in_bb with entry exit and def range

Split the old functionality of ssa_name_in_bb into the components for
definition in a block, entry and exit range.  Call these as appropriate.

	* gimple-range-cache.cc (ranger_cache::ssa_range_in_bb): Delete.
	(ranger_cache::range_of_def): New.
	(ranger_cache::entry_range): New.
	(ranger_cache::exit_range): New.
	(ranger_cache::range_of_expr): Adjust.
	(ranger_cache::range_on_edge): Adjust.
	(ranger_cache::propagate_cache): Call exit_range directly.
	* gimple-range-cache.h (class ranger_cache): Adjust.