nand_imx: fix "used uninitialized" warning on mx25
drivers/nand/nand_imx.c: In function 'imx_nand_load_image':
drivers/nand/nand_imx.c:1074: warning: 'host' is used uninitialized in this function
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>