Fix a potentially uninitialised variable in SELinux hooks that's given a
pointer to the network address by selinux_parse_skb() passing a pointer back
through its argument list.  By restructuring selinux_parse_skb(), the compiler
can see that the error case need not set it as the caller will return
immediately.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NJames Morris <jmorris@namei.org>