drm/radeon: properly track the crtc not_enabled case evergreen_mc_stop()

The save struct is not initialized previously so explicitly
mark the crtcs as not used when they are not in use.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

drivers/gpu/drm/radeon/evergreen.c

@@ -1330,6 +1330,8 @@ void evergreen_mc_stop(struct radeon_device *rdev, struct evergreen_mc_save *sav
 					break;
 				udelay(1);
 			}
+		} else {
+			save->crtc_enabled[i] = false;
 		}
 	}