Add misalignment output parameter to get_load_store_type

Add misalignment output parameter to get_load_store_type

This makes us compute the misalignment alongside the alignment support
scheme in get_load_store_type, removing some out-of-place calls to
the DR alignment API.

2021-10-18  Richard Biener  <rguenther@suse.de>

	* tree-vect-stmts.c (get_group_load_store_type): Add
	misalignment output parameter and initialize it.
	(get_group_load_store_type): Likewise.
	(vectorizable_store): Remove now redundant queries.
	(vectorizable_load): Likewise.