sunxi: axp: Support VBUS drive GPIO on AXP818

AXP818 supports VBUS drive function, even though the manual does not
mention it.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

include/axp818.h

@@ -55,7 +55,11 @@
 
 /* For axp_gpio.c */
 #define AXP_POWER_STATUS		0x00
-#define AXP_POWER_STATUS_VBUS_PRESENT	(1 << 5)
+#define AXP_POWER_STATUS_VBUS_PRESENT		(1 << 5)
+#define AXP_VBUS_IPSOUT			0x30
+#define AXP_VBUS_IPSOUT_DRIVEBUS		(1 << 2)
+#define AXP_MISC_CTRL			0x8f
+#define AXP_MISC_CTRL_N_VBUSEN_FUNC		(1 << 4)
 #define AXP_GPIO0_CTRL			0x90
 #define AXP_GPIO1_CTRL			0x92
 #define AXP_GPIO_CTRL_OUTPUT_LOW	0x00 /* Drive pin low */