libpayload: Add support for the CBMEM in memory console.

Change-Id: I1489b5306ef1ca078686fed4dba2d242f70ad941
Signed-off-by: Gabe Black <gabeblack@google.com>
Reviewed-on: http://review.coreboot.org/1727
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

payloads/libpayload/Config.in

@@ -147,6 +147,10 @@ endmenu
 
 menu "Console Options"
 
+config CBMEM_CONSOLE
+	bool "Send output to the in memory CBMEM console"
+	default y
+
 config SERIAL_CONSOLE
 	bool "See output on the serial port console"
 	default y