vld1 was calling set_neon_register with the wrong size for register. We
follow the pseudocode implementation in the manual, by splatting the
value into a d register, and writing to the list of registers in a loop.

Bug: chromium:1092059
Change-Id: I2ce594594cd59347c20b88926f8ecc18ef9d5514
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2238506Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68297}