Revert "UCLOUDNG-812 : remove force_config_drive option in nova.conf on all cnodes"

This reverts commit c803c23de821dad870cf9fc2249b2478a3261f4d.
UCLOUDNG-812 : remove force_config_drive option in nova.conf on all cnodes
Merge pull request #50 from chamankang/UCLOUDNG-812

Ucloudng 812