Remove limit on the number of renderer processes

This CL removes the limit to the number of renderer processes that can
be created. This allows the browser to utilize more system resources and
potentially improve performance, especially on devices with many cores
and ample memory.

Bug: 369342694

Change-Id: I06108675a86d6fa83687f4f09a98a4fa095c8e53
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5875002
Reviewed-by: Charlie Reis <creis@chromium.org>
Reviewed-by: Francois Pierre Doray <fdoray@chromium.org>
Commit-Queue: Alex Attar <aattar@google.com>
Cr-Commit-Position: refs/heads/main@{#1363146}