Get the board-specific dependencies right.

Currently each board is dumping all of its config options regardless of
whether we are even on the right architecture or not (this is due to
outright sourcing of the configs at the upper level..). Dependency
resolution either needs to be done there, or at the board-specific level.

target/device/AMD/Config.in

@@ -1,4 +1,5 @@
 comment "AMD Specific Device Support"
+	depends BR2_mipsel || BR2_mips
 
 config BR2_TARGET_AMD_ALCHEMY
 	bool "Board support for the AMD development boards"
@@ -15,10 +16,13 @@ config BR2_TARGET_AMD_ALCHEMY_DBAU1500
 	help
 	  The AMD Alchemy DBAu1500 Development Board
 
+comment "Package support"
+	depends BR2_TARGET_AMD_ALCHEMY
+
 config BR2_PACKAGE_LINUX
 	bool "linux"
 	default n
+	depends BR2_TARGET_AMD_ALCHEMY
 	help
 	    The Linux kernel.
 	    http://www.kernel.org/
-

target/device/Soekris/Config.in

@@ -6,8 +6,12 @@ config BR2_TARGET_SOEKRIS_NET4521
 	help
 	  The Soekris net4521
 
+comment "Package support"
+	depends on BR2_TARGET_SOEKRIS_NET4521
+
 config BR2_PACKAGE_LINUX
 	bool "linux"
+	depends on BR2_TARGET_SOEKRIS_NET4521
 	default n
 	help
 	    The Linux kernel.