Description of problem:

Considering ctime is a client side feature, we can't blindly load ctime xlator into the client graph if it's explicitly turned off, that'd result into backward compatibility issue where an old client can't mount a volume configured on a server which is having ctime feature.

Since ctime feature is enabled by default, any old client would still fail to connect to a new server until and unless this feature is turned off explicitly. Any client side feature when marked as enabled by default means there's a need to either turn of the feature if old client is to be made work with new servers or client needs to be upgraded to the latest version of server.

Version-Release number of selected component (if applicable):

Server >= release-6, client <= release-5

How reproducible:
Always

Steps to Reproduce:
1. Create a volume on glusterfs-5 or higher
2. Mount the volume from a client which is running any version lower than glusterfs-5
3. Mount doesn't go through

Actual results:
Mount fails

Expected results:
Mount shouldn't fail



Additional info: