[media] tda7432: Fix setting TDA7432_MUTE bit for TDA7432_RF register

Fix a copy-paste bug when converting to the control framework.

Fixes: commit 5d478e0d ("[media] tda7432: convert to the control framework")
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/i2c/tda7432.c

@@ -293,7 +293,7 @@ static int tda7432_s_ctrl(struct v4l2_ctrl *ctrl)
 		if (t->mute->val) {
 			lf |= TDA7432_MUTE;
 			lr |= TDA7432_MUTE;
-			lf |= TDA7432_MUTE;
+			rf |= TDA7432_MUTE;
 			rr |= TDA7432_MUTE;
 		}
 		/* Mute & update balance*/