Easize is just too wierd.  allow Eaddrlen, too.  next step (undone)
is to get rid of Easize.

Reference: /n/atom/patch/applied2013/fsipeaddrlen
Date: Tue Aug 27 16:01:44 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/fs/ip/ip.h	Tue Aug 27 16:01:17 2013
+++ /sys/src/fs/ip/ip.h	Tue Aug 27 16:01:18 2013
@@ -9,6 +9,7 @@
 enum
 {
 	Easize		= 6,		/* Ether address size */
+	Eaddrlen	= 6,
 	Pasize		= 4,		/* IP protocol address size */
 };