[6PACK]: Masking bug in 6pack driver.

Looks like a broken masking to me, binary not is used where bitwise
not was intended.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/hamradio/6pack.c

@@ -914,7 +914,7 @@ static void decode_prio_command(struct sixpack *sp, unsigned char cmd)
 					printk(KERN_DEBUG "6pack: protocol violation\n");
 				else
 					sp->status = 0;
-				cmd &= !SIXP_RX_DCD_MASK;
+				cmd &= ~SIXP_RX_DCD_MASK;
 		}
 		sp->status = cmd & SIXP_PRIO_DATA_MASK;
 	} else { /* output watchdog char if idle */