TT#73210 Use grml2usb v0.14.14 when handling grml64-small_2018.04.11-efi.iso

grml2usb <=0.14.14 works when building with ISO grml64-small_2018.04.11-efi.
Newer grml2usb versions provide SecureBoot support (which was introduced in
grml2usb v0.16.0). This is failing with our grml64-small_2018.04.11-efi ISO
though, because its provided EFI image doesn't contain a valid/mountable FAT
file system:

| % file /tmp/grml2iso.tmp/grml2usb55ey_q68/boot/efi.img
| /tmp/grml2iso.tmp/grml2usb55ey_q68/boot/efi.img: PE32+ executable (EFI application) x86-64 (stripped to external PDB), for MS Windows

Whereas the efi file from more recent Grml(-Sipwise) ISOs like
https://deb.sipwise.com/deployment-iso/grml/grml-sipwise-buster-20191022_addons.iso
looks like this:

| % file /mnt/test1/boot/efi.img
| /mnt/test1/boot/efi.img: DOS/MBR boot sector, code offset 0x3c+2, OEM-ID "mkfs.fat", sectors/cluster 4, root entries 512, sectors 8192 (volumes <=32 MB) , Media descriptor 0xf8, sectors/FAT 6, sectors/track 32, heads 64, serial number 0xef681600, label: "GRML       ", FAT (12 bit)

and can be properly mounted for further adjusting by grml2usb/grml2iso.

So use grml2usb version v0.17.0 except when handling ISO
grml64-small_2018.04.11-efi ISO, then we use the version we had available on
our Debian/stretch environments back then, AKA grml2usb v0.14.14.

Change-Id: I452d7cbac138d59dc11fb1773ca3d6f6c307a6df
(cherry picked from commit 608dd03674)

build_iso.sh

@@ -13,6 +13,7 @@ TEMPLATES="templates"
 GRML_URL="${GRML_URL:-https://deb.sipwise.com/files/grml/}"
 GRML_HASH_URL="${GRML_HASH_URL:-https://deb.sipwise.com/files/grml/}"
 SIPWISE_ISO="sip_provider_${MR}_${DATE}.iso"
+GRML2USB_VERSION='v0.17.0'
 
 usage () {
   echo "Usage: $0 compat <grml.iso> <mr version> <Debian dist>"
@@ -46,6 +47,12 @@ else
 fi
 
 echo "*** Building ${MR} ISO ***"
+case "${GRML_ISO}" in
+  grml64-small_2018.04.11-efi*)
+    GRML2USB_VERSION='v0.14.14'
+    echo "*** NOTE: identified Grml ISO ${GRML_ISO}, falling back to grml2usb version ${GRML2USB_VERSION} for building"
+    ;;
+esac
 
 echo "*** Retrieving Grml ISO [${GRML_ISO}] ***"
 # shellcheck disable=SC2086
@@ -77,7 +84,6 @@ cp ${TEMPLATES}/boot/isolinux/isolinux.cfg ${TEMPLATES}/boot/isolinux/syslinux.c
 echo "*** Generating Sipwise ISO ***"
 
 if [[ ! -d grml2usb.git ]] ; then
-  GRML2USB_VERSION='v0.17.0'
   if ! git clone -b "${GRML2USB_VERSION}" --single-branch --depth 1 https://github.com/grml/grml2usb grml2usb.git ; then
     echo "Cloning grml2usb from github failed, falling back to git.grml.org"
     git clone -b "${GRML2USB_VERSION}" --single-branch --depth 1 git://git.grml.org/grml2usb.git