USB: fix usbatm tiny race

ia64:

drivers/usb/atm/usbatm.c: In function `usbatm_do_heavy_init':
drivers/usb/atm/usbatm.c:1004: warning: implicit declaration of function `get_current'
drivers/usb/atm/usbatm.c:1004: error: invalid type argument of `->'
Signed-off-by: Duncan Sands <baldrick@free.fr>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/atm/usbatm.c

@@ -1001,7 +1001,7 @@ static int usbatm_do_heavy_init(void *arg)
 
 	daemonize(instance->driver->driver_name);
 	allow_signal(SIGTERM);
-	instance->thread_pid = get_current()->pid;
+	instance->thread_pid = current->pid;
 
 	complete(&instance->thread_started);