[ATM]: net/atm/ioctl.c should #include "common.h"

Every file should #include the header files containing the prototypes
of it's global functions.

common.h contains the prototype for vcc_ioctl().

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>