net: fix kernel-doc warnings in header files

Add missing structure kernel-doc descriptions to sock.h & skbuff.h
to fix kernel-doc warnings.

(I think that Stephen H. sent a similar patch, but I can't find it.
I just want to kill the warnings, with either patch.)

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 412672a7..bbd8d00 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -232,6 +232,8 @@
  *	@mark: Generic packet mark
  *	@nfct: Associated connection, if any
  *	@ipvs_property: skbuff is owned by ipvs
+ *	@peeked: this packet has been seen already, so stats have been
+ *		done for it, don't do them again
  *	@nf_trace: netfilter packet trace flag
  *	@nfctinfo: Relationship of this skb to the connection
  *	@nfct_reasm: netfilter conntrack re-assembly pointer