[ARM] Fix Kconfig breakage in arch/arm/mach-iop3xx/Kconfig

When a "depends" statement against all configuration options of a choice,
which causes all options of that choice to be disabled, it sends Kconfig
into an infinite loop.  Move the "depends" clause to the choice statement
instead.

arch/arm/mach-iop3xx/Kconfig

@@ -4,17 +4,16 @@ menu "IOP3xx Implementation Options"
 choice
 	prompt "IOP3xx System Type"
 	default ARCH_IQ80310
+	depends on ARCH_IOP3XX
 
 config ARCH_IQ80310
 	bool "IQ80310"
-	depends on ARCH_IOP3XX
 	help
 	  Say Y here if you want to run your kernel on the Intel IQ80310
 	  evaluation kit for the IOP310 chipset.
 
 config ARCH_IQ80321
 	bool "IQ80321"
-	depends on ARCH_IOP3XX
 	help
 	  Say Y here if you want to run your kernel on the Intel IQ80321
 	  evaluation kit for the IOP321 chipset.