drm/amdgpu: fix the hibernation suspend with s0ix

drm/amdgpu: fix the hibernation suspend with s0ix

BugLink: https://bugs.launchpad.net/bugs/1922601
commit 9aa26019c1a60013ea866d460de6392acb1712ee upstream.

During system hibernation suspend still need un-gate gfx CG/PG firstly to handle HW
status check before HW resource destory.

Signed-off-by: Prike Liang <Prike.Liang@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>