power: axp818: Remove undefined axp818_init()

axp818_init() is declared, but never defined.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Reviewed-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NHans de Goede <hdegoede@redhat.com>

include/axp818.h

@@ -53,8 +53,6 @@
 #define AXP818_ALDO2_CTRL	0x29
 #define AXP818_ALDO3_CTRL	0x2a
 
-int axp818_init(void);
-
 /* For axp_gpio.c */
 #define AXP_POWER_STATUS		0x00
 #define AXP_POWER_STATUS_VBUS_PRESENT	(1 << 5)