Simplify grub_efi_path on redhat family

[eb4x]

Remains backwards-compatible with supported distros, and we don't have to look for openeuler or oraclelinux or any other EL variant.

[ekohl]

I recently dove into the (patched) source and confirmed it the lower case ID from /etc/os-release. This is a close approximation.

[m-bucher]

@ekohl @eb4x I must object at least in part to this PR, because I actually install foreman on OracleLinux from time to time.

I am not sure if there is a better way to fix this than just reverting this commit (which is what I currently do).

[ekohl]

@m-bucher I think this shouldn't break Oracle, unless the name in /etc/os-release differs from the Puppet fact name. Because that's how grub2 on Red Hat is patched: use the name from os-release (downcased) in the file path

[eb4x]

Unfortunately, he's right. I installed OracleLinux 8.9 on an efi vm. It's /boot/efi/EFI/redhat, because why the 🤬 wouldn't it be.

Would this be an ok way to write an exception for this exceptional os?

$grub_efi_path = unless $facts['os']['name'] == 'OracleLinux' {
    downcase($facts['os']['name'])
} else {
  'redhat'
}

[ekohl]

I would use a regular if instead of unless, but yes. This is (sadly) going to be needed

[eb4x]

I "reverted" back to the previous way with the case statement, with the logic swapped. #828