freescale: common: pfuze: define pfuze_mode_init only if defined(CONFIG_DM_PMIC)

pfuze_mode_init calls pmic_reg_read which is only available from

obj-$(CONFIG_$(SPL_TPL_)DM_PMIC) += pmic-uclass.o

Prepare for conversion of defined(CONFIG_DM_PMIC) to
CONFIG_IS_ENABLED(DM_PMIC).

Signed-off-by: Troy Kisky <troykiskyboundary@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

board/freescale/common/pfuze.c

@@ -91,7 +91,7 @@ struct pmic *pfuze_common_init(unsigned char i2cbus)
 
 	return p;
 }
-#else
+#elif defined(CONFIG_DM_PMIC)
 int pfuze_mode_init(struct udevice *dev, u32 mode)
 {
 	unsigned char offset, i, switch_num;