This pblendw/movlhps combination has lower latency and requires less
unop than pinsrq (1 v.s. 2).

Bug: v8:11589
Change-Id: I770b0c20a286774afefbac5ef0adffe463318f21
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2828871Reviewed-by: Bill Budge <bbudge@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74049}