This CL is a port of https://crrev.com/c/3045349 for ia32 and arm,
adding helper methods to drop arguments from the stack.

Drive-by: Add RootAsOperand to ia32.

Bug: v8:11112
Change-Id: I07b753d51b9fc9fc91bf09618b1315d146827123
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3069157Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Patrick Thier <pthier@chromium.org>
Cr-Commit-Position: refs/heads/master@{#76095}