securityfs: do not depend on CONFIG_SECURITY

Add a new Kconfig option SECURITYFS which will build securityfs support
but does not require CONFIG_SECURITY.  The only current user of
securityfs does not depend on CONFIG_SECURITY and there is no reason the
full LSM needs to be built to build this fs.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/Kconfig b/security/Kconfig
index 5592939..d9f47ce 100644
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -51,6 +51,14 @@
 
 	  If you are unsure how to answer this question, answer N.
 
+config SECURITYFS
+	bool "Enable the securityfs filesystem"
+	help
+	  This will build the securityfs filesystem.  It is currently used by
+	  the TPM bios character driver.  It is not used by SELinux or SMACK.
+
+	  If you are unsure how to answer this question, answer N.
+
 config SECURITY_NETWORK
 	bool "Socket and Networking Security Hooks"
 	depends on SECURITY