drm/amdgpu/uvd3.x: fix register definition warnings

drop the duplicate register macros from sid.h and use the
standard ones in the oss register headers.

Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/si.c

@@ -44,6 +44,7 @@
 #include "dce_virtual.h"
 #include "gca/gfx_6_0_d.h"
 #include "oss/oss_1_0_d.h"
+#include "oss/oss_1_0_sh_mask.h"
 #include "gmc/gmc_6_0_d.h"
 #include "dce/dce_6_0_d.h"
 #include "uvd/uvd_4_0_d.h"