mx51evk: Fix pmic_init() argument

On mx51evk board the PMIC is connected via SPI interface, so it does not make
sense to pass I2C_PMIC into the pmic_init() interface.

Pass the SPI bus number via CONFIG_FSL_PMIC_BUS option instead.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Stefano Babic <sbabic@denx.de>

board/freescale/mx51evk/mx51evk.c

@@ -174,7 +174,7 @@ static void power_init(void)
 	struct pmic *p;
 	int ret;
 
-	ret = pmic_init(I2C_PMIC);
+	ret = pmic_init(CONFIG_FSL_PMIC_BUS);
 	if (ret)
 		return;