usb: gadget: net2272: use false for 'use_dma'

Fix the following coccicheck warning:

drivers/usb/gadget/udc/net2272.c:57:12-19: WARNING: Assignment of 0/1 to
bool variable
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

drivers/usb/gadget/udc/net2272.c

@@ -54,7 +54,7 @@ static const char * const ep_name[] = {
  *
  * If use_dma is disabled, pio will be used instead.
  */
-static bool use_dma = 0;
+static bool use_dma = false;
 module_param(use_dma, bool, 0644);
 
 /*