analyzer: simplify sm_state_map lookup

analyzer: simplify sm_state_map lookup

gcc/analyzer/ChangeLog:
	* engine.cc (impl_region_model_context::get_malloc_map): Replace
	with...
	(impl_region_model_context::get_state_map_by_name): ...this.
	(impl_region_model_context::get_fd_map): Delete.
	(impl_region_model_context::get_taint_map): Delete.
	* exploded-graph.h (impl_region_model_context::get_fd_map):
	Delete.
	(impl_region_model_context::get_malloc_map): Delete.
	(impl_region_model_context::get_taint_map): Delete.
	(impl_region_model_context::get_state_map_by_name): New.
	* region-model.h (region_model_context::get_state_map_by_name):
	New vfunc.
	(region_model_context::get_fd_map): Convert from vfunc to
	function.
	(region_model_context::get_malloc_map): Likewise.
	(region_model_context::get_taint_map): Likewise.
	(noop_region_model_context::get_state_map_by_name): New.
	(noop_region_model_context::get_fd_map): Delete.
	(noop_region_model_context::get_malloc_map): Delete.
	(noop_region_model_context::get_taint_map): Delete.
	(region_model_context_decorator::get_state_map_by_name): New.
	(region_model_context_decorator::get_fd_map): Delete.
	(region_model_context_decorator::get_malloc_map): Delete.
	(region_model_context_decorator::get_taint_map): Delete.

Signed-off-by: David Malcolm <dmalcolm@redhat.com>