drm/amdgpu: Add decode_iv_ts helper for ih_v6 block

Was missing.  Add it.
Signed-off-by: Harish Kasiviswanathan <Harish.Kasiviswanathan@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/ih_v6_0.c

@@ -727,6 +727,7 @@ static const struct amd_ip_funcs ih_v6_0_ip_funcs = {
 static const struct amdgpu_ih_funcs ih_v6_0_funcs = {
 	.get_wptr = ih_v6_0_get_wptr,
 	.decode_iv = amdgpu_ih_decode_iv_helper,
+	.decode_iv_ts = amdgpu_ih_decode_iv_ts_helper,
 	.set_rptr = ih_v6_0_set_rptr
 };