[atomic-devel] always use /etc/default/grub when update grub.cfg

[Vasiliy Tolstov <v tolstov selfip ru>]

I have custom /etc/default/grub modified after install kernel cmdline.
But when i deploy new ostree i always have old kernel cmdline.

I'm retest with _OSTREE_GRUB2_BOOTVERSION=X grub2-mkconfig (x -0 or 1
getted via readlink /boot/loader) and always have ostree composed
cmdline =(

-- 
Vasiliy Tolstov,
e-mail: v tolstov selfip ru