imx-drm: ipuv3-plane: Use %pad to print 'dma_addr_t'

Fix the following static checker warning:

drivers/staging/imx-drm/ipuv3-plane.c:75:2: warning: format '%x' expects argument of type 'unsigned int', but argument 4 has type 'dma_addr_t' [-Wformat]

Use %pad to print 'dma_addr_t'.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>