Fix GRUB2 loader commands for Debian/Ubuntu

Back in time, GRUB2 is using `linux` and `initrd` loader commands to
load the kernel and initrd into ram on legacy BIOS. Later, `linuxefi`
and `initrdefi` loader commands have been added to do the same on UEFI
platforms as some kind of interim solution. These out-of-tree patches
have been added by the vendors.

First vendors [1] started now to drop patches for `linuxefi`/`initrdefi`
loader commands support, `linux`/`initrd` of course also work under UEFI
then.

Thus, we need to adapt preseed templates to render correct templates
with supported loader commands.

[1]:https://salsa.debian.org/grub-team/grub/-/commit/5cf01c9d98bda554ac2460a6e68e34743a19328f

app/views/unattended/provisioning_templates/PXEGrub2/preseed_default_pxegrub2.erb

@@ -19,7 +19,7 @@ description: |
   os_major = @host.operatingsystem.major.to_i
   os_name  = @host.operatingsystem.name
 
-  if (os_name == 'Ubuntu' && os_major > 12) || (os_name == 'Debian' && os_major > 8)
+  if (os_name == 'Ubuntu' && os_major > 12 && os_major < 24) || (os_name == 'Debian' && os_major > 8 && os_major < 13)
     efi_suffix = 'efi'
   else
     efi_suffix = ''

app/views/unattended/provisioning_templates/PXEGrub2/preseed_default_pxegrub2_autoinstall.erb

@@ -19,7 +19,13 @@ test_on:
 #   System locale
 #
 <%
-  efi_suffix = 'efi'
+  os_major = @host.operatingsystem.major.to_i
+
+  if (os_major > 12 && os_major < 24)
+    efi_suffix = 'efi'
+  else
+    efi_suffix = ''
+  end
 -%>
 
 set default=0