orion5x: kconfig: move board select menu and common settings

Becuase the board select menu in arch/arm/Kconfig is too big,
move the Orion5x board select menu to orion5x/Kconfig.

Move also common settings (CONFIG_SYS_CPU="arm926ejs" and
CONFIG_SYS_SOC="orion5x").

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>

board/LaCie/edminiv2/Kconfig

@@ -1,9 +1,5 @@
 if TARGET_EDMINIV2
 
-config SYS_CPU
-	string
-	default "arm926ejs"
-
 config SYS_BOARD
 	string
 	default "edminiv2"
@@ -12,10 +8,6 @@ config SYS_VENDOR
 	string
 	default "LaCie"
 
-config SYS_SOC
-	string
-	default "orion5x"
-
 config SYS_CONFIG_NAME
 	string
 	default "edminiv2"