Revert "drm/amdgpu: stop scheduler when calling hw_fini (v2)"

This reverts commit f7d6779d.

This bisected regression has impacted suspend-resume stability
since 5.15-rc1. It regressed -stable via 5.14.10.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215315
Fixes: f7d6779d

 ("drm/amdgpu: stop scheduler when calling hw_fini (v2)")
Cc: Guchun Chen <guchun.chen@amd.com>
Cc: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: <stable@vger.kernel.org> # 5.14+
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>