Host group parameter inheritance is not functional for the `kernelcmd` parameter on Red Hat Satellite 6.x

Issue

• Host group parameter inheritance is not functional for the kernelcmd parameter on Red Hat Satellite 6.x.

  For example, if I set kernelcmd=ipv6.disable=1 on the parent host group, and kernelcmd=nouveau.modeset=0 rd.driver.blacklist=nouveau on the child host group, I do not end up with kernelcmd=ipv6.disable=1 nouveau.modeset=0 rd.driver.blacklist=nouveau on the host associated with the child host group.