Staging: emxx_udc: Return NULL instead of 0.

Return NULL instead of 0 from nbu2ss_ep_alloc_request(),if req pointer is NULL.

---
Changes in v2:
* No change.
*Compile emxx_udc directory to check nothing is broken.

 drivers/staging/emxx_udc/emxx_udc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index d38673c..e8cacae 100644
@@ -2625,7 +2625,7 @@ static struct usb_request *nbu2ss_ep_alloc_request(
 
 	req = kzalloc(sizeof(*req), gfp_flags);
 	if (!req)
-		return 0;
+		return NULL;
 
 #ifdef USE_DMA
 	req->req.dma = DMA_ADDR_INVALID;

1.8.3.4