Similar to removing synchronized_ from the object macros[1], we can do
it for RELAXED_SMI_ACCESSORS and use the corresponding relaxed tags.

Bug: v8:7790
Change-Id: Iafc0ed9587e30df0b83565b2976522c4aa634c63
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2880535Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74465}