sunxi: add support for Banana Pi M2 Plus board

Banana Pi M2 Plus is an Allwinner H3-based SBC by Sinovoip, which has
already mainline device tree file that have landed into U-Boot source
tree.

Add a defconfig file for it and add the MAINTAINERS items.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Reviewed-by: Jagan Teki <jagan@openedev.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>

board/sunxi/MAINTAINERS

@@ -280,6 +280,11 @@ S:	Maintained
 F:	configs/Sinlinx_SinA33_defconfig
 W:	http://linux-sunxi.org/Sinlinx_SinA33
 
+SINOVOIP BPI M2 PLUS H3 BOARD
+M:	Icenowy Zheng <icenowy@aosc.io>
+S:	Maintained
+F:	configs/Sinovoip_BPI_M2_Plus_defconfig
+
 SINOVOIP BPI M3 A83T BOARD
 M:	VishnuPatekar <vishnupatekar0510@gmail.com>
 S:	Maintained

configs/Sinovoip_BPI_M2_Plus_defconfig

+CONFIG_ARM=y
+CONFIG_ARCH_SUNXI=y
+CONFIG_MACH_SUN8I_H3=y
+CONFIG_DRAM_CLK=672
+CONFIG_DRAM_ZQ=3881979
+CONFIG_DRAM_ODT_EN=y
+CONFIG_MACPWR="PD6"
+CONFIG_MMC_SUNXI_SLOT_EXTRA=2
+CONFIG_DEFAULT_DEVICE_TREE="sun8i-h3-bananapi-m2-plus"
+# CONFIG_SYS_MALLOC_CLEAR_ON_INIT is not set
+CONFIG_CONSOLE_MUX=y
+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_SUN8I_EMAC=y
+CONFIG_USB_EHCI_HCD=y