SELinux: remove inherit field from inode_security_struct

Remove inherit field from inode_security_struct, per Stephen Smalley:
"Let's just drop inherit altogether - dead field."
Signed-off-by: James Morris <jmorris@namei.org>

security/selinux/include/objsec.h

@@ -43,7 +43,6 @@ struct inode_security_struct {
 	u32 sid;		/* SID of this object */
 	u16 sclass;		/* security class of this object */
 	unsigned char initialized;	/* initialization flag */
-	unsigned char inherit;	/* inherit SID from parent entry */
 	struct mutex lock;
 };