analyzer: handle arrays of unknown size in access diagrams [PR113222]

gcc/analyzer/ChangeLog:
	PR analyzer/113222
	* access-diagram.cc (valid_region_spatial_item::add_boundaries):
	Handle TYPE_DOMAIN being null.
	(valid_region_spatial_item::add_array_elements_to_table):
	Likewise.

gcc/testsuite/ChangeLog:
	PR analyzer/113222
	* gcc.dg/analyzer/out-of-bounds-diagram-pr113222.c: New test.

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