net: cosmetic: Un-typedef Ethernet_t

Separate the Ethernet header from the 802 header.
Base the size constants on the structs.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/net/bootp.c b/net/bootp.c
index b8d2760..3285250 100644
--- a/net/bootp.c
+++ b/net/bootp.c
@@ -103,7 +103,7 @@
 	NetCopyIP(&tmp_ip, &bp->bp_siaddr);
 	if (tmp_ip != 0)
 		NetCopyIP(&NetServerIP, &bp->bp_siaddr);
-	memcpy(NetServerEther, ((Ethernet_t *)NetRxPacket)->et_src, 6);
+	memcpy(NetServerEther, ((struct ethernet_hdr *)NetRxPacket)->et_src, 6);
 #endif
 	if (strlen(bp->bp_file) > 0)
 		copy_filename(BootFile, bp->bp_file, sizeof(BootFile));