Map::bit_field needs to be set with relaxed store. The concurrent marker
accesses the has_prototype_slot bit in Map::bit_field to calculate
header size.

Bug: v8:10315
Change-Id: Ie7ebb9316b8c703adfddf10df25949b872ce0c8d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2194012Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67728}