tboot kernel installed, on a system with tboot disabled, after yum update

Hello,

I had a new RHEL 6.6 x86_64 installation with tboot enabled. I decided I didn't want tboot so I disabled it be following instructions of https://access.redhat.com/solutions/421093 document. The problem is that after a "yum update" and the installation of a new kernel, kernel description in grub.conf includes the tboot portion which leads to server not booting since tboot package has been removed. I suppose that during the "yum update" process something done during the initial installation (with tboot enable) triggers the creation of a grub.conf entry with the tboot portion. Is there any way to avoid that and eventually not having to edit grub.conf after every new kernel installation?

Thanks,
Evagelos