freerdp: separate GatewayUsageMethod from GatewayEnabled
Merge branch 'master' of git://github.com/awakecoding/FreeRDP

# By Marc-André Moreau
# Via Marc-André Moreau
* 'master' of git://github.com/awakecoding/FreeRDP:
  freerdp: separate GatewayUsageMethod from GatewayEnabled