Avoid premature alignment setting in vect_duplicate_ssa_name_ptr_info

Avoid premature alignment setting in vect_duplicate_ssa_name_ptr_info

This removes adjusting alignment based on the vectorized accesses
and instead keeps what was set on the original access.  The
code generating the actual accesses make sure to properly align
the vectorized accesses based on the generated pointer already
and the vectorizers alignment is always based of the desired
alignment of a vector type and thus will reset alignment to
unknown this way for example when doing strided accesses.

2021-09-20  Richard Biener  <rguenther@suse.de>

	* tree-vect-data-refs.c (vect_duplicate_ssa_name_ptr_info):
	Do not compute alignment of the vectorized access here.