sunxi: Add defconfig for Allwinner A23 EVB

This enables the support for the Allwinner A23 Evaluation Board (EVB),
that already had a device tree (from Linux) but no defconfig.

This board has an AXP223 PMIC, some NAND, Audio out and in plugs, an
accelerometer and light sensor, as well as a USB HSIC hub and a USB
OTG mini-USB connector. It also has a Wifi/BT chip.

Access to the other buses (LCD, MIPI DSI, LVDS, etc) can be done
through dedicated pin headers.

Signed-off-by: Florent Jacquet <florent.jacquet@free-electrons.com>
Cc: Jagan Teki <jagan@openedev.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

configs/sun8i_a23_evb_defconfig

@@ -0,0 +1,19 @@
+CONFIG_ARM=y
+CONFIG_ARCH_SUNXI=y
+CONFIG_MACH_SUN8I_A23=y
+CONFIG_DRAM_CLK=552
+CONFIG_DRAM_ZQ=63351
+CONFIG_USB0_VBUS_PIN="axp_drivebus"
+CONFIG_USB0_VBUS_DET="axp_vbus_detect"
+CONFIG_USB1_VBUS_PIN="PH7"
+CONFIG_DEFAULT_DEVICE_TREE="sun8i-a23-evb"
+# CONFIG_SYS_MALLOC_CLEAR_ON_INIT is not set
+CONFIG_SYS_EXTRA_OPTIONS="CONS_INDEX=5"
+CONFIG_SPL=y
+# CONFIG_CMD_IMLS is not set
+# CONFIG_CMD_FLASH is not set
+# CONFIG_CMD_FPGA is not set
+# CONFIG_SPL_DOS_PARTITION is not set
+# CONFIG_SPL_ISO_PARTITION is not set
+# CONFIG_SPL_EFI_PARTITION is not set
+CONFIG_USB_EHCI_HCD=y