RecordWrite uses callee saved registers, so only the clobbered registers
need to be saved by the caller.
This change gives us a 1% reduction in embedded blob size for arm64.
No change is seen for arm as the STM instruction can store and load
multiple registers.

Change-Id: I8e41da43851e96d3454a01c7093d76f2e0378214
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3406744Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Martyn Capewell <martyn.capewell@arm.com>
Cr-Commit-Position: refs/heads/main@{#78900}