drm/amdgpu: remove unused variable ring

building with gcc and W=1 reports
drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c:81:29: error: variable
  ‘ring’ set but not used [-Werror=unused-but-set-variable]
   81 |         struct amdgpu_ring *ring;
      |                             ^~~~

ring is not used so remove it.
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c

@@ -78,12 +78,10 @@ static void vcn_v4_0_set_ras_funcs(struct amdgpu_device *adev);
 static int vcn_v4_0_early_init(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
-	struct amdgpu_ring *ring;
 
 	if (amdgpu_sriov_vf(adev)) {
 		adev->vcn.harvest_config = VCN_HARVEST_MMSCH;
 		for (int i = 0; i < adev->vcn.num_vcn_inst; ++i) {
-			ring = &adev->vcn.inst[i].ring_enc[0];
 			if (amdgpu_vcn_is_disabled_vcn(adev, VCN_ENCODE_RING, i)) {
 				adev->vcn.harvest_config |= 1 << i;
 				dev_info(adev->dev, "VCN%d is disabled by hypervisor\n", i);