vect: Call vect_convert_output with the right vecitype [PR114108]

This patch fixes a bug where vect_recog_abd_pattern called vect_convert_output
with the incorrect vecitype for the corresponding pattern_stmt.
vect_convert_output expects vecitype to be the vector form of the scalar type
of the LHS of pattern_stmt, but we were passing in the vector form of the LHS
of the new impending conversion statement.  This caused a skew in ABD's
pattern_stmt having the vectype of the following gimple pattern_stmt.

	2024-03-06  Tejas Belagod  <tejas.belagod@arm.com>

gcc/ChangeLog:

	PR middle-end/114108
	* tree-vect-patterns.cc (vect_recog_abd_pattern): Call
	vect_convert_output with the correct vecitype.

gcc/testsuite/ChangeLog:
	* gcc.dg/vect/pr114108.c: New test.