lorax: Provide correct device information to xen.efi

xen.efi needs to call EFI services to access kernel and initramfs
images. For that it needs correct device handle. Grub set it to 'root'
device, regardless of which device was really used to load xen.efi.

lorax-templates-qubes/templates/config_files/x86/grub2-efi.cfg

@@ -20,11 +20,13 @@ set timeout=5
 
 search --no-floppy --set=root -l '@ISOLABEL@'
 
-menuentry 'Test media and install @PRODUCT@ @VERSION@' --class fedora --class gnu-linux --class gnu --class os {
+menuentry 'Test media and install @PRODUCT@ @VERSION@' --class qubes --class gnu-linux --class gnu --class os {
+    search --no-floppy --set=root -l 'ANACONDA'
     chainloader @EFIDIR@/xen.efi placeholder qubes-check
 }
 
-menuentry 'Install @PRODUCT@ @VERSION@' --class fedora --class gnu-linux --class gnu --class os {
+menuentry 'Install @PRODUCT@ @VERSION@' --class qubes --class gnu-linux --class gnu --class os {
+    search --no-floppy --set=root -l 'ANACONDA'
     chainloader @EFIDIR@/xen.efi
 }