intel: Make monotonic timer a first class citizen

The monotonic time now needs to be a first class citizen in Coreboot as
it is a hard dependency of the drivers/spi flash command polling
function.

Change-Id: I4e43d2680bf84bc525138f71c2b813b0f6be5265
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/6135
Tested-by: build bot (Jenkins)
Reviewed-by: David Hendricks <dhendrix@chromium.org>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>

src/northbridge/intel/nehalem/Kconfig

@@ -25,6 +25,7 @@ config NORTHBRIDGE_INTEL_NEHALEM
 	select DYNAMIC_CBMEM
 	select VGA
 	select INTEL_EDID
+	select TSC_MONOTONIC_TIMER
 
 if NORTHBRIDGE_INTEL_NEHALEM