testsuite/vect: Make match patterns more accurate.

testsuite/vect: Make match patterns more accurate.

On some targets we fail to vectorize with the first type the vectorizer
tries but succeed with the second.  This patch changes several regex
patterns to reflect that behavior.

Before we would look for a single occurrence of e.g.
"vect_recog_dot_prod_pattern" but would possible have two (one for each
attempted mode).  The new pattern tries to match sequences where we
first have a "vect_recog_dot_prod_pattern" and a "succeeded" afterwards
while making sure there is no "failed" or "Re-trying" in between.

gcc/testsuite/ChangeLog:

	* gcc.dg/vect/vect-outer-4c-big-array.c: Adjust regex pattern.
	* gcc.dg/vect/vect-reduc-dot-s16a.c: Ditto.
	* gcc.dg/vect/vect-reduc-dot-s8a.c: Ditto.
	* gcc.dg/vect/vect-reduc-dot-s8b.c: Ditto.
	* gcc.dg/vect/vect-reduc-dot-u16a.c: Ditto.
	* gcc.dg/vect/vect-reduc-dot-u16b.c: Ditto.
	* gcc.dg/vect/vect-reduc-dot-u8a.c: Ditto.
	* gcc.dg/vect/vect-reduc-dot-u8b.c: Ditto.
	* gcc.dg/vect/vect-reduc-pattern-1a.c: Ditto.
	* gcc.dg/vect/vect-reduc-pattern-1b-big-array.c: Ditto.
	* gcc.dg/vect/vect-reduc-pattern-1c-big-array.c: Ditto.
	* gcc.dg/vect/vect-reduc-pattern-2a.c: Ditto.
	* gcc.dg/vect/vect-reduc-pattern-2b-big-array.c: Ditto.
	* gcc.dg/vect/wrapv-vect-reduc-dot-s8b.c: Ditto.