kconfig: automatically include mainboards

This change switches all mainboard vendors and mainboards
to be autoincluded by Kconfig, rather than having to be mentioned
explicitly.

This means, vendor and mainboard directories are becoming more
"drop in", e.g. be placed in the coreboot directory hierarchy
without having to modify any higher level coreboot files.

The long term plan is to enable out of tree mainboards / components
to be built with a given coreboot version (given that the API did
not change)

Signed-off-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Change-Id: Ib68ce1478a2e12562aeac6297128a21eb174d58a
Reviewed-on: http://review.coreboot.org/9295
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/mainboard/ibm/Kconfig

@@ -3,15 +3,11 @@ if VENDOR_IBM
 choice
 	prompt "Mainboard model"
 
-config BOARD_IBM_E325
-	bool "eServer 325"
-config BOARD_IBM_E326
-	bool "eServer 326"
+source "src/mainboard/ibm/*/Kconfig.name"
 
 endchoice
 
-source "src/mainboard/ibm/e325/Kconfig"
-source "src/mainboard/ibm/e326/Kconfig"
+source "src/mainboard/ibm/*/Kconfig"
 
 config MAINBOARD_VENDOR
 	string

src/mainboard/ibm/Kconfig.name

@@ -0,0 +1,2 @@
+config VENDOR_IBM
+	bool "IBM"

src/mainboard/ibm/e325/Kconfig.name

@@ -0,0 +1,2 @@
+config BOARD_IBM_E325
+	bool "eServer 325"

src/mainboard/ibm/e326/Kconfig.name

@@ -0,0 +1,2 @@
+config BOARD_IBM_E326
+	bool "eServer 326"