Liftoff currently allocates a stack frame of fixed size for each
function, and bails out if more stack space is needed during code
generation for the function.
This CL prepares the interface and the assemblers on ia32 and x64 to
allow patching of the stack frame size after the whole function body
was generated.

R=mstarzinger@chromium.org, titzer@chromium.org
CC=sreten.kovacevic@mips.com

Bug: v8:6600
Change-Id: Iff54ff65f3e6e13d53ff90ec34b2c5cf7d276d5e
Reviewed-on: https://chromium-review.googlesource.com/925463
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51406}