soc/intel/quark: Fix serial port configuration

Fix serial port configuration broken by how PCI configuration space was
referenced introduced by change 3d15e10a (MMCONF_SUPPORT: Flip default
to enabled).

TEST=Build and run on Galileo Gen2

Change-Id: I2ab52cf598795e94f1f16977f8d12b7fdd95e146
Signed-off-by: Lee Leahy <leroy.p.leahy@intel.com>
Reviewed-on: https://review.coreboot.org/17984
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Martin Roth <martinroth@google.com>

src/soc/intel/quark/Kconfig

@@ -29,6 +29,7 @@ config CPU_SPECIFIC_OPTIONS
 	select BOOTBLOCK_SAVE_BIST_AND_TIMESTAMP
 	select C_ENVIRONMENT_BOOTBLOCK
 	select HAVE_HARD_RESET
+	select NO_MMCONF_SUPPORT
 	select REG_SCRIPT
 	select RELOCATABLE_RAMSTAGE
 	select SOC_INTEL_COMMON
@@ -40,6 +41,10 @@ config CPU_SPECIFIC_OPTIONS
 	select UNCOMPRESSED_RAMSTAGE
 	select USE_MARCH_586
 
+config MMCOMF_SUPPORT_DEFAULT
+	bool
+	default n
+
 #####
 # Debug serial output
 #     The following options configure the debug serial port