SELinux: Only store the network interface's ifindex

Instead of storing the packet's network interface name store the ifindex.  This
allows us to defer the need to lookup the net_device structure until the audit
record is generated meaning that in the majority of cases we never need to
bother with this at all.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/selinux/include/avc.h b/security/selinux/include/avc.h
index 553607a..80c28fa 100644
--- a/security/selinux/include/avc.h
+++ b/security/selinux/include/avc.h
@@ -51,7 +51,7 @@
 			struct inode *inode;
 		} fs;
 		struct {
-			char *netif;
+			int netif;
 			struct sock *sk;
 			u16 family;
 			__be16 dport;