apparmor: Mark alloc_unconfined() as static

Kernel test robot throws below warning ->
security/apparmor/policy_ns.c:83:20: warning: no previous prototype
for function 'alloc_unconfined' [-Wmissing-prototypes]

Mark it as static.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Souptick Joarder (HPE) <jrdr.linux@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

security/apparmor/policy_ns.c

@@ -80,7 +80,7 @@ const char *aa_ns_name(struct aa_ns *curr, struct aa_ns *view, bool subns)
 	return aa_hidden_ns_name;
 }
 
-struct aa_profile *alloc_unconfined(const char *name)
+static struct aa_profile *alloc_unconfined(const char *name)
 {
 	struct aa_profile *profile;