[eepro100] Do not discard short packets

In a virtual environment such as qemu, we can legitimately receive
packets less than 64 bytes in length, such as ARP replies.  These are
currently discarded, causing most IPv4 communication to fail.

Fix by ignoring the RFDShort bit when receiving packets.

Reported-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/drivers/net/eepro100.c

 		       cur_rx );
 		DBGIO_HD ( (void*)rfd->packet, 0x30 );
 
-		if ( ( status & RFD_STATUS ) != RFD_OK ) {
+		if ( ( status & ( RFD_STATUS & ~RFDShort ) ) != RFD_OK ) {
 			DBG ( "Corrupted packet received. "
 			      "Status = %#08hx\n", status );
 			netdev_rx_err ( netdev, iob, -EINVAL );