Add entries for the 100base-FX full and half duplex supported modes.
$ ethtool eth0
Supported ports: [ FIBRE ]
Supported link modes: 100baseFX/Half 100baseFX/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: No
Supported FEC modes: Not reported
Advertised link modes: 100baseFX/Half 100baseFX/Full
Advertised pause frame use: No
Advertised auto-negotiation: No
Advertised FEC modes: Not reported
Speed: 100Mb/s
Duplex: Full
Auto-negotiation: off
Port: MII
PHYAD: 1
Transceiver: external
Supports Wake-on: gs
Wake-on: d
SecureOn password: 00:00:00:00:00:00
Current message level: 0x00000000 (0)
Link detected: yes
Signed-off-by: Dan Murphy <dmurphy@xxxxxx>