It was previously only passed to compilation units in src/bigint/,
but inconsistencies arise when it's not passed to other compilation
units that #include src/bigint/bigint.h.

Fixed: chromium:1233397
Change-Id: Idb310d8c13bad12766699086574aa2c3869eb56c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3056452Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75941}