[media] si2168: add one missing parenthesis

Fix following warnings:
si2168_cmd_execute() warn: add some parenthesis here?
si2168_cmd_execute() warn: maybe use && instead of &

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/dvb-frontends/si2168.c

@@ -60,7 +60,7 @@ static int si2168_cmd_execute(struct si2168 *s, struct si2168_cmd *cmd)
 				jiffies_to_msecs(jiffies) -
 				(jiffies_to_msecs(timeout) - TIMEOUT));
 
-		if (!(cmd->args[0] >> 7) & 0x01) {
+		if (!((cmd->args[0] >> 7) & 0x01)) {
 			ret = -ETIMEDOUT;
 			goto err_mutex_unlock;
 		}