Fix PR81362: Vector peeling

Fix PR81362: Vector peeling

npeel was erroneously overwritten by vect_peeling_hash_get_lowest_cost
although the corresponding dataref is not used afterwards.  It should
be safe to get rid of the npeel parameter since we use the returned
peeling_info's npeel anyway.  Also removed the body_cost_vec parameter
which is not used elsewhere.

gcc/ChangeLog:

2017-07-18  Robin Dapp  <rdapp@linux.vnet.ibm.com>

	* tree-vect-data-refs.c (vect_enhance_data_refs_alignment): Remove
	body_cost_vec from _vect_peel_extended_info.
	(vect_peeling_hash_get_lowest_cost): Do not set body_cost_vec.
	(vect_peeling_hash_choose_best_peeling): Remove body_cost_vec and
	npeel.

From-SVN: r250300