Revert "drm/amdgpu/gfx10: enlarge CP_MEC_DOORBELL_RANGE_UPPER to cover full doorbell."

Revert "drm/amdgpu/gfx10: enlarge CP_MEC_DOORBELL_RANGE_UPPER to cover full doorbell."

commit baacf52a473b24e10322b67757ddb92ab8d86717 upstream.

This reverts commit 1c0b0efd148d5b24c4932ddb3fa03c8edd6097b3.

Reason for revert: Side effect of enlarging CP_MEC_DOORBELL_RANGE may
cause some APUs fail to enter gfxoff in certain user cases.

Signed-off-by: Yifan Zhang <yifan1.zhang@amd.com>
Acked-by: Alex Deucher <alexander.deucher@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>