server: set max htlc in ChannelUpdate createChannelUpdate
server: set max htlc in ChannelUpdate createChannelUpdate

This method is called to convert an EdgePolicy to a ChannelUpdate. We
make sure to carry over the max_htlc value.

Co-authored-by: Johan T. Halseth <313b7951f9319f7c5b8c372fa32d29abbc4e9236@gmail.com>

LightningNetwork/lnd,aakselrod/lnd,LightningNetwork/lnd,aakselrod/lnd