Add a kernel option for use when LiveCD's are being built.

This setting should be used in our own kernel patches where we need to alter
behaviour for kernels that will be used for booting on LiveCD's.
First example is siimage-no-sata.patch.

Against gentoo-dev-sources-2.6.5-r1.

- Daniel Drake <dsd@gentoo.org>

--- linux-2.6.5-gentoo-r1/init/Kconfig	2004-05-19 15:44:47.000000000 +0100
+++ linux-2.6.5-gentoo-r1-dsd/init/Kconfig	2004-05-19 15:57:03.434063920 +0100
@@ -228,6 +228,16 @@ config CC_OPTIMIZE_FOR_SIZE
 
 	  If unsure, say N.
 
+config GENTOO_LIVECD
+	bool "Build for Gentoo LiveCD"
+	default n
+	help
+	  Select this option if you are compiling a kernel to be used for
+	  bootup of a Gentoo LiveCD. This does not apply if you are compiling
+	  for a standard Gentoo-based system.
+
+	  If unsure, say N.
+
 endmenu		# General setup