drm/vc4: Fix definition of QPU_R_MS_REV_FLAGS

We don't use it in shader validation currently, so it had no effect,
but best to fix it anyway in case we do some day.
Signed-off-by: NEric Anholt <eric@anholt.net>

drivers/gpu/drm/vc4/vc4_qpu_defines.h

@@ -70,7 +70,7 @@ enum qpu_raddr {
 	QPU_R_ELEM_QPU = 38,
 	QPU_R_NOP,
 	QPU_R_XY_PIXEL_COORD = 41,
-	QPU_R_MS_REV_FLAGS = 41,
+	QPU_R_MS_REV_FLAGS = 42,
 	QPU_R_VPM = 48,
 	QPU_R_VPM_LD_BUSY,
 	QPU_R_VPM_LD_WAIT,