Without simple FP aliasing, a SIMD register will overlap with two
floating-point registers. If we spill an FP register to use it for a
SIMD operation, we need to make sure to also spill the "sibling" FP
register.

R=leszeks@chromium.org

Bug: v8:12330, chromium:1271244
Change-Id: I7fdc6cb8da35d66b4862a8a913ba4ff906cf05aa
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3347576Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78414}