The cgroup_enable parameter is a Raspberry Pi kernel specific kernel
parameter. Upstream based kernel do not have the parameter, and hence
do not do anything.
This gets rid of the following message during boot:
Unknown kernel command line parameters "cgroup_enable=memory", will be passed to user space.
* Retry up to 3 times
By default, HAOS used to retry 3 times. That is still true for U-Boot
based boards. Apply the same logic for GRUB2 based systems for
consistency.
This can help to remedy intermittent internet/connectivity issuese.
Altough hacky, in practise it makes sense to give the newly installed OS
another go.
* Also apply to generic-aarch64
This aligns with what we used to have in Barebox. Most of the time the
user is not expected to make a choice, so keeping the timeout short is
sensible.
