gianfar: remove definition of DEBUG

Defining DEBUG should only be done in development.
So remove DEBUG.
Signed-off-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20210113215603.1721958-1-trix@redhat.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/freescale/gianfar.c

@@ -58,7 +58,6 @@
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-#define DEBUG
 
 #include <linux/kernel.h>
 #include <linux/string.h>