board: amlogic: factorise gxbb boards

The nanopi-k2 and the odroid-c2 are similar enough to be supported
by the same u-boot board. This change use odroid-c2 u-boot board
for the nanopi-k2 as well. Dedicated defconfig are kept to customize
the names and device tree.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
diff --git a/arch/arm/mach-meson/Kconfig b/arch/arm/mach-meson/Kconfig
index 98303db..d86b1be 100644
--- a/arch/arm/mach-meson/Kconfig
+++ b/arch/arm/mach-meson/Kconfig
@@ -31,14 +31,7 @@
 	  ODROID-C2 is a single board computer based on Meson GXBaby
 	  with 2 GiB of RAM, Gigabit Ethernet, HDMI, 4 USB, micro-SD
 	  slot, eMMC, IR receiver and a 40-pin GPIO header.
-
-config TARGET_NANOPI_K2
-	bool "NANOPI_K2"
-	select MESON_GXBB
-	help
-	  NANOPI_K2 is a single board computer based on Meson GXBaby
-	  with 2 GiB of RAM, Gigabit Ethernet,AP6212 Wifi, HDMI, 4 USB,
-	  micro-SD slot, eMMC, IR receiver and a 40-pin GPIO header.
+	  You should also select this TARGET if you have an nanopi-k2
 
 config TARGET_P212
 	bool "P212"
@@ -69,8 +62,6 @@
 
 source "board/amlogic/odroid-c2/Kconfig"
 
-source "board/amlogic/nanopi-k2/Kconfig"
-
 source "board/amlogic/p212/Kconfig"
 
 source "board/amlogic/q200/Kconfig"