media: dvb-usb-v2: af9035: fix ISO C90 compilation error on af9035_i2c_master_xfer

This fixes a 'ISO C90 forbids mixed declarations and code' compilation
error on af9035_i2c_master_xfer, which is caused by the sanity check added
on user controlled msg[i], before declaring the demodulator register.

Fixes: 7bf744f ("media: dvb-usb-v2: af9035: Fix null-ptr-deref in af9035_i2c_master_xfer")
Signed-off-by: Desnes Nunes <desnesn@redhat.com>
Link: https://lore.kernel.org/r/20240919172755.196907-1-desnesn@redhat.com
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

Author: Desnes Nunes

drivers/media/usb/dvb-usb-v2/af9035.c

@@ -322,13 +322,16 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap,
 			ret = -EOPNOTSUPP;
 		} else if ((msg[0].addr == state->af9033_i2c_addr[0]) ||
 			   (msg[0].addr == state->af9033_i2c_addr[1])) {
+			/* demod access via firmware interface */
+			u32 reg;
+
 			if (msg[0].len < 3 || msg[1].len < 1) {
 				ret = -EOPNOTSUPP;
 				goto unlock;
 			}
-			/* demod access via firmware interface */
-			u32 reg = msg[0].buf[0] << 16 | msg[0].buf[1] << 8 |
-					msg[0].buf[2];
+
+			reg = msg[0].buf[0] << 16 | msg[0].buf[1] << 8 |
+				msg[0].buf[2];
 
 			if (msg[0].addr == state->af9033_i2c_addr[1])
 				reg |= 0x100000;
@@ -385,13 +388,16 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap,
 			ret = -EOPNOTSUPP;
 		} else if ((msg[0].addr == state->af9033_i2c_addr[0]) ||
 			   (msg[0].addr == state->af9033_i2c_addr[1])) {
+			/* demod access via firmware interface */
+			u32 reg;
+
 			if (msg[0].len < 3) {
 				ret = -EOPNOTSUPP;
 				goto unlock;
 			}
-			/* demod access via firmware interface */
-			u32 reg = msg[0].buf[0] << 16 | msg[0].buf[1] << 8 |
-					msg[0].buf[2];
+
+			reg = msg[0].buf[0] << 16 | msg[0].buf[1] << 8 |
+				msg[0].buf[2];
 
 			if (msg[0].addr == state->af9033_i2c_addr[1])
 				reg |= 0x100000;