drivers/net/ethernet/ibm/ehea/ehea_main.c: add alias entry for portN properties

Use separate table for alias entries in the ehea module, otherwise the
probe() function will operate on the separate ports instead of the
lhea-"root" entry of the device-tree

Addresses https://bugzilla.novell.com/show_bug.cgi?id=435215



[ Thadeu notes that: "... this issue might happen with the generation of
  initrd, when the scripts check for /sys/class/net/eth0/device/modalias,
  which links to the port device at
  /sys/devices/ibmebus/23c00400.lhea/port0/" ]

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Olaf Hering <ohering@suse.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>