security: fix description of values returned by cap_inode_need_killpriv

cap_inode_need_killpriv returns 1 if security.capability exists and
has a value and inode_killpriv() is required, 0 otherwise. Fix the
description of the return value to reflect this.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

security/commoncap.c

@@ -300,10 +300,10 @@ static inline void bprm_clear_caps(struct linux_binprm *bprm)
  *
  * Determine if an inode having a change applied that's marked ATTR_KILL_PRIV
  * affects the security markings on that inode, and if it is, should
- * inode_killpriv() be invoked or the change rejected?
+ * inode_killpriv() be invoked or the change rejected.
  *
- * Returns 0 if granted; +ve if granted, but inode_killpriv() is required; and
- * -ve to deny the change.
+ * Returns 1 if security.capability has a value, meaning inode_killpriv()
+ * is required, 0 otherwise, meaning inode_killpriv() is not required.
  */
 int cap_inode_need_killpriv(struct dentry *dentry)
 {