Revert "drm/amd: flush any delayed gfxoff on suspend entry"

commit 91636168 upstream.

commit ab475033 ("drm/amdgpu/sdma5.2: add begin/end_use ring
callbacks") caused GFXOFF control to be used more heavily and the
codepath that was removed from commit 0dee7263 ("drm/amd: flush any
delayed gfxoff on suspend entry") now can be exercised at suspend again.

Users report that by using GNOME to suspend the lockscreen trigger will
cause SDMA traffic and the system can deadlock.

This reverts commit 0dee7263.

Acked-by: Alex Deucher <alexander.deucher@amd.com>
Fixes: ab475033 ("drm/amdgpu/sdma5.2: add begin/end_use ring callbacks")
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>