In the same vein we did tagged stores, we can do tagged loads.

As a drive-by, move GetTSANRelaxedStoreStub to CodeFactory.

Bug: v8:7790, v8:11600
Change-Id: Ic1ef3245623756538eab64c3358047e3797195c1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2953162
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75145}