[ARM,MVE] Add missing tests for vqdmlash intrinsics.

Summary:
These were accidentally left out of D76123. I added tests for the
other three instructions in this small cross-product family (vqdmlah,
vqrdmlah, vqrdmlash) but missed this one.

Reviewers: miyuki

Reviewed By: miyuki

Subscribers: kristof.beyls, dmgreen, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76714