drm/amd/vcn: fix an error msg on vcn 3.0

Some video card has more than one vcn instance, passing 0 to
vcn_v3_0_pause_dpg_mode is incorrect.

Error msg:
Register(1) [mmUVD_POWER_STATUS] failed to reach value
0x00000001 != 0x00000002
Reviewed-by: James Zhu <James.Zhu@amd.com>
Signed-off-by: tiancyin <tianci.yin@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c

@@ -1488,7 +1488,7 @@ static int vcn_v3_0_stop_dpg_mode(struct amdgpu_device *adev, int inst_idx)
 	struct dpg_pause_state state = {.fw_based = VCN_DPG_STATE__UNPAUSE};
 	uint32_t tmp;
 
-	vcn_v3_0_pause_dpg_mode(adev, 0, &state);
+	vcn_v3_0_pause_dpg_mode(adev, inst_idx, &state);
 
 	/* Wait for power status to be 1 */
 	SOC15_WAIT_ON_RREG(VCN, inst_idx, mmUVD_POWER_STATUS, 1,