[apparmor] constify struct path * in a bunch of helpers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index dec607c..9713037 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -149,7 +149,7 @@
  *
  * Returns: %0 else error code if error or permission denied
  */
-static int common_perm(int op, struct path *path, u32 mask,
+static int common_perm(int op, const struct path *path, u32 mask,
 		       struct path_cond *cond)
 {
 	struct aa_profile *profile;