usb: gadget: net2272: fix compile warnings

This patch fixes the following compile warnings:

drivers/usb/gadget/net2272.c: In function ‘net2272_kick_dma’:
drivers/usb/gadget/net2272.c:740:2: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 6 has type ‘dma_addr_t’ [-Wformat]
drivers/usb/gadget/net2272.c: In function ‘net2272_queue’:
drivers/usb/gadget/net2272.c:859:2: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 8 has type ‘dma_addr_t’ [-Wformat]

Signed-off-by: Felipe Balbi <balbi@ti.com>