add missing deps on python(3)-pbr (rhbz#1346054)
    
    python-detect misses a requires on python-pbr.
    This means hardware-detect won't run if only python-detect is installed
    but not python-hardware
    
    Also the python3-hardware sub package has a BR on python3-pbr but doesn't
    requires it at runtime (unlike the python2 package)
    
    Change-Id: Ia88d7ad1aa0363fad2b4c2c2163b5cc85d382ad8