SELinux: turn mount options strings into defines

Convert the strings used for mount options into #defines rather than
retyping the string throughout the SELinux code.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

security/selinux/include/security.h

@@ -41,6 +41,11 @@
 #define ROOTCONTEXT_MNT	0x04
 #define DEFCONTEXT_MNT	0x08
 
+#define CONTEXT_STR	"context="
+#define FSCONTEXT_STR	"fscontext="
+#define ROOTCONTEXT_STR	"rootcontext="
+#define DEFCONTEXT_STR	"defcontext="
+
 struct netlbl_lsm_secattr;
 
 extern int selinux_enabled;