net: usb: Using workqueue as bottom half handler

usbnet driver uses tasklet as bottom half handler. Since tasklet
runs in interrupt context in case of high throughput driver is
spending more time in interrupt context to process rx buffers
this is causing watch dog reset. Hence replace the tasklet with
workqueue to avoid watchdog reset.

CRs-Fixed: 378526
Change-Id: I8eac339e37d734dbaaf7a2e874d3974f562e8680
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>
diff --git a/include/linux/usb/usbnet.h b/include/linux/usb/usbnet.h
index 76f4396..72f5c96 100644
--- a/include/linux/usb/usbnet.h
+++ b/include/linux/usb/usbnet.h
@@ -56,7 +56,7 @@
 	struct sk_buff_head	rxq_pause;
 	struct urb		*interrupt;
 	struct usb_anchor	deferred;
-	struct tasklet_struct	bh;
+	struct work_struct	bh_w;
 
 	struct work_struct	kevent;
 	unsigned long		flags;