bblayer-hob.conf currently does not define enough variables or have enough functionality for it to be used in place of bblayers.conf. So we need to improve bblayers-hob.conf to better match bblayers.conf. Or, another better approach can be designed to replace bblayers-hob.conf. Note: this feature originates from bug 3001.
Now Hob use directly bblayers.conf from build/conf directory(according to #2934). I will mark this one obsolete.
Verified.