drm/amdgpu: use register distance member instead of hardcode in UVD7/VCE4

This patch updates to use register distance member instead of hardcode
in UVD7/VCE4. They are for the same ASIC.

Signed-off-by: Huang Rui <[e-mail]>
Tested-by: AnZhong Huang <[e-mail]>
Reviewed-by: Christian König <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/amdgpu/uvd_v7_0.c

···
 	pd_addr = amdgpu_gmc_emit_flush_gpu_tlb(ring, vmid, pd_addr);
 
 	/* wait for reg writes */
-	data0 = hub->ctx0_ptb_addr_lo32 + vmid * 2;
+	data0 = hub->ctx0_ptb_addr_lo32 + vmid * hub->ctx_addr_distance;
 	data1 = lower_32_bits(pd_addr);
 	mask = 0xffffffff;
 	uvd_v7_0_ring_emit_reg_wait(ring, data0, data1, mask);
···
 	pd_addr = amdgpu_gmc_emit_flush_gpu_tlb(ring, vmid, pd_addr);
 
 	/* wait for reg writes */
-	uvd_v7_0_enc_ring_emit_reg_wait(ring, hub->ctx0_ptb_addr_lo32 + vmid * 2,
+	uvd_v7_0_enc_ring_emit_reg_wait(ring, hub->ctx0_ptb_addr_lo32 +
+					vmid * hub->ctx_addr_distance,
 					lower_32_bits(pd_addr), 0xffffffff);
 }
 

drivers/gpu/drm/amd/amdgpu/vce_v4_0.c

···
 	pd_addr = amdgpu_gmc_emit_flush_gpu_tlb(ring, vmid, pd_addr);
 
 	/* wait for reg writes */
-	vce_v4_0_emit_reg_wait(ring, hub->ctx0_ptb_addr_lo32 + vmid * 2,
+	vce_v4_0_emit_reg_wait(ring, hub->ctx0_ptb_addr_lo32 +
+			       vmid * hub->ctx_addr_distance,
 			       lower_32_bits(pd_addr), 0xffffffff);
 }