selinux: sparse fix: make selinux_secmark_refcount static

Sparse fix: make selinux_secmark_refcount  static.

Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 266a229..e07cf7f 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -96,7 +96,7 @@
 extern struct security_operations *security_ops;
 
 /* SECMARK reference count */
-atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
+static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 
 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 int selinux_enforcing;