Turn vect_create_addr_base_for_vector_ref offset into a byte offset

Turn vect_create_addr_base_for_vector_ref offset into a byte offset

This changes the offset in elements for vect_create_addr_base_for_vector_ref
and vect_create_data_ref_ptr to an offset in bytes, easing a following
refactoring.

2021-10-26  Richard Biener  <rguenther@suse.de>

	* tree-vect-data-refs.c (vect_create_addr_base_for_vector_ref):
	Take offset in bytes.
	(vect_create_data_ref_ptr): Likewise.
	* tree-vect-loop-manip.c (get_misalign_in_elems): Multiply
	offset by element size.
	(vect_create_cond_for_align_checks): Likewise.
	* tree-vect-stmts.c (get_negative_load_store_type): Likewise.
	(vectorizable_load): Remove duplicate leftover from merge
	conflict.