staging: comedi: remove unnecessary '#define _GNU_SOURCE'

This define is not needed.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers.c

@@ -21,8 +21,6 @@
 
 */
 
-#define _GNU_SOURCE
-
 #define __NO_VERSION__
 #include <linux/device.h>
 #include <linux/module.h>

drivers/staging/comedi/drivers/ni_65xx.c

@@ -48,7 +48,6 @@ except maybe the 6514.
 
  */
 
-#define _GNU_SOURCE
 #define DEBUG 1
 #define DEBUG_FLAGS
 #include <linux/interrupt.h>