drm/amdgpu: set Vega20 LBPW as disabled at default

For Vega20, LBPW feature is disabled at default.
Signed-off-by: NEvan Quan <evan.quan@amd.com>
Reviewed-by: NFeifei Xu <Feifei.Xu@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c

@@ -2499,6 +2499,20 @@ static int gfx_v9_0_rlc_resume(struct amdgpu_device *adev)
 			return r;
 	}
 
+	if (amdgpu_lbpw == -1) {
+		switch (adev->asic_type) {
+		case CHIP_RAVEN:
+			amdgpu_lbpw = 1;
+			break;
+		case CHIP_VEGA20:
+			amdgpu_lbpw = 0;
+			break;
+		default:
+			amdgpu_lbpw = 0;
+			break;
+		}
+	}
+
 	if (adev->asic_type == CHIP_RAVEN ||
 	    adev->asic_type == CHIP_VEGA20) {
 		if (amdgpu_lbpw != 0)