keymile: Make distinct kmeter1, and kmcoge5ne configs

The kmeter1, and kmcoge5ne boards also build from the same config
file with #ifdef logic.

Create a separate include config for each board with the #ifdef logic
resolved as needed.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
diff --git a/configs/kmcoge5ne_defconfig b/configs/kmcoge5ne_defconfig
index cb47b0b..b7c42fa 100644
--- a/configs/kmcoge5ne_defconfig
+++ b/configs/kmcoge5ne_defconfig
@@ -1,10 +1,9 @@
 CONFIG_PPC=y
 CONFIG_SYS_TEXT_BASE=0xF0000000
 CONFIG_MPC83xx=y
-CONFIG_TARGET_KM8360=y
+CONFIG_TARGET_KMCOGE5NE=y
 CONFIG_OF_BOARD_SETUP=y
 CONFIG_OF_STDOUT_VIA_ALIAS=y
-CONFIG_SYS_EXTRA_OPTIONS="KMCOGE5NE"
 CONFIG_MISC_INIT_R=y
 CONFIG_VERSION_VARIABLE=y
 CONFIG_BOARD_EARLY_INIT_R=y