Revert "ANDROID: cgroup: Add android_rvh_cgroup_force_kthread_migration"

This reverts commit d4f032e3 as it
causes merge conflicts in 6.0-rc2.

If it is still needed in an Android kernel release, it can be added back
into a release-specific branch at a later point in time.

Bug: 184594949
Cc: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Cc: Shaleen Agrawal <shalagra@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I5d2ff43a1e4e14308c41cfd5d2d752836a134ae0