This CL introduces TurboAssembler::LoadTaggedPointerField() and
TurboAssembler::LoadAnyTaggedField(), which respectively loads a field
containing a HeapObject, or any tagged value, and decompresses it if necessary.

Bug: v8:7703
Change-Id: I71ace74d7433a3a78d56bdcef6d2ec041df630e4
Reviewed-on: https://chromium-review.googlesource.com/c/1456098
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59501}