net: dev: Use unsigned integer as an argument to left-shift

1 << 31 is Undefined Behaviour according to the C standard.
Use U type modifier to avoid theoretical overflow.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/netdevice.h

@@ -3861,7 +3861,7 @@ static inline u32 netif_msg_init(int debug_value, int default_msg_enable_bits)
 	if (debug_value == 0)	/* no output */
 		return 0;
 	/* set low N bits */
-	return (1 << debug_value) - 1;
+	return (1U << debug_value) - 1;
 }
 
 static inline void __netif_tx_lock(struct netdev_queue *txq, int cpu)