Remove FSP Rangeley SOC and mohonpeak board support

mohonpeak is the reference board for Rangeley. I doubt anyone uses it
or cares about it. We jokingly refer to it as "Moron Peak". It's code
with no known users, so we shouldn't be hauling it around for the
eventuality that someone might use it in the future.

Change-Id: Id3c9fc39e1b98707d96a95f2a914de6bbb31c615
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-on: http://review.coreboot.org/11790
Tested-by: build bot (Jenkins)
Reviewed-by: Philipp Deppenwiese <zaolin@das-labor.org>

src/vendorcode/intel/Kconfig

@@ -20,7 +20,6 @@
 config FSP_VENDORCODE_HEADER_PATH
 	string
 	default "fsp1_0/baytrail" if SOC_INTEL_FSP_BAYTRAIL
-	default "fsp1_0/rangeley" if CPU_INTEL_FSP_MODEL_406DX
 
 config UEFI_2_4_BINDING
 	def_bool n