nvram: Add option to reset NVRAM to default parameters on every boot

In specific configurations, such as homogeneous supercomputing systems,
changeable NVRAM parameters are more of a liability than a useful tool.
This patch allows a coreboot image to be compiled that will always set
the NVRAM parameters to their default values, reducing maintainance
overhead on large clusters.

Change-Id: Ic03e34211d4a58cd60740f2d9a6b50e11fe85822
Signed-off-by: Timothy Pearson <tpearson@raptorengineeringinc.com>
Reviewed-on: http://review.coreboot.org/8446
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>

src/Kconfig

@@ -116,6 +116,15 @@ config USE_OPTION_TABLE
 	  Enable this option if coreboot shall read options from the "CMOS"
 	  NVRAM instead of using hard-coded values.
 
+config STATIC_OPTION_TABLE
+	bool "Load default configuration values into CMOS on each boot"
+	default n
+	depends on USE_OPTION_TABLE
+	help
+	  Enable this option to reset "CMOS" NVRAM values to default on
+	  every boot.  Use this if you want the NVRAM configuration to
+	  never be modified from its default values.
+
 config COMPRESS_RAMSTAGE
 	bool "Compress ramstage with LZMA"
 	default y