net/miiphy/serial: drop duplicate "NAMESIZE" define

A few subsystems are using the same define "NAMESIZE".  This has been
working so far because they define it to the same number.  However, I
want to change the size of eth_device's NAMESIZE, so rather than tweak
the define names, simply drop references to it.  Almost no one does,
and the handful that do can easily be changed to a sizeof().

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/board/Marvell/db64460/mv_eth.c b/board/Marvell/db64460/mv_eth.c
index 4aefbaf..a763d79 100644
--- a/board/Marvell/db64460/mv_eth.c
+++ b/board/Marvell/db64460/mv_eth.c
@@ -221,7 +221,7 @@
 			return;
 		}
 
-		/* must be less than NAMESIZE (16) */
+		/* must be less than sizeof(dev->name) */
 		sprintf (dev->name, "mv_enet%d", devnum);
 
 #ifdef DEBUG