Typically, the utilization on a given AP-105 is much much less than the 100Mbps mark. e.g. a 100Mbps port DOES NOT limit you.
What does? Typically the egress connection to the internet... e.g. if all users are doing is hitting the internet, the likelyhood that they will overwhelm a 100Mbps connection is very low. So there is no penalty to running in 100Mbps and no special items we need to do.
You can use Airwave to tell you what the utilization is AP by AP, user by user, radio by radio and determine what the loading is on your network. Likely under 100Mbps per AP ;)
JF