selinux: make selinuxfs_mount static

It is not referenced outside selinuxfs.c, so remove its extern header
declaration and make it static.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

security/selinux/include/security.h

@@ -436,7 +436,6 @@ extern void selinux_complete_init(void);
 extern int selinux_disable(struct selinux_state *state);
 extern void exit_sel_fs(void);
 extern struct path selinux_null;
-extern struct vfsmount *selinuxfs_mount;
 extern void selnl_notify_setenforce(int val);
 extern void selnl_notify_policyload(u32 seqno);
 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);

security/selinux/selinuxfs.c

@@ -2204,7 +2204,7 @@ static struct file_system_type sel_fs_type = {
 	.kill_sb	= sel_kill_sb,
 };
 
-struct vfsmount *selinuxfs_mount;
+static struct vfsmount *selinuxfs_mount;
 struct path selinux_null;
 
 static int __init init_sel_fs(void)