isolinux: fix toram=... variable usage within isolinux configs

Fixup for commit 9453222, where we introduced usage of
$fixed_squashfs_name.  This variable was set up only *after*
adjust_boot_files function got invoked for the isolinux configuration
files. As a result the isolinux configuration files ended up with their
template placeholder settings included ("toram=%SQUASHFS_NAME%").

Fix ordering, but also warn in adjust_boot_files() if the the
$fixed_squashfs_name + $fixed_release_info variables are unset.

Thanks: Chris Hofstaedtler for the bug report
Closes: grml/grml#179

grml-live

@@ -347,9 +347,13 @@ adjust_boot_files() {
       sed -i "s/%GRML_NAME%/$GRML_NAME/g"          "${file}"
       if [ -n "${fixed_squashfs_name}" ] ; then
         sed -i "s/%SQUASHFS_NAME%/${fixed_squashfs_name}/g" "${file}"
+      else
+        ewarn "Variable fixed_squashfs_name is unset, can't adjust %SQUASHFS_NAME% in templates." ; eend 1
       fi
       if [ -n "${fixed_release_info}" ] ; then
         sed -i "s/%RELEASE_INFO%/${fixed_release_info}/g"   "${file}"
+      else
+        ewarn "Variable fixed_release_info is unset, can't adjust %RELEASE_INFO% in templates." ; eend 1
       fi
       sed -i "s/%SHORT_NAME%/$SHORT_NAME/g"        "${file}"
       sed -i "s/%VERSION%/$VERSION/g"              "${file}"
@@ -1231,6 +1235,15 @@ if [ "$ARCH" = i386 ] || [ "$ARCH" = amd64 ] ; then
 
     # make sure the squashfs filename is set accordingly:
     SQUASHFS_NAME="$GRML_NAME.squashfs"
+    # adjust bootsplash accordingly but make sure the string has the according length
+    fixed_squashfs_name="$(cut_string 20 "$SQUASHFS_NAME")"
+    fixed_squashfs_name="$(extend_string_end 20 "$fixed_squashfs_name")"
+    for file in f4 f5 ; do
+      if [ -r "${BUILD_OUTPUT}/boot/isolinux/${file}" ] ; then
+        sed -i "s/%SQUASHFS_NAME%/${fixed_squashfs_name}/" "${BUILD_OUTPUT}/boot/isolinux/${file}"
+        sed -i "s/%SQUASHFS_NAME%/${fixed_squashfs_name}/" "${BUILD_OUTPUT}/boot/isolinux/${file}"
+      fi
+    done
 
     # adjust all variables in the templates with the according distribution information
     adjust_boot_files "${BUILD_OUTPUT}"/boot/isolinux/*.cfg \
@@ -1245,16 +1258,6 @@ if [ "$ARCH" = i386 ] || [ "$ARCH" = amd64 ] ; then
       done
     done
 
-    # adjust bootsplash accordingly but make sure the string has the according length
-    fixed_squashfs_name="$(cut_string 20 "$SQUASHFS_NAME")"
-    fixed_squashfs_name="$(extend_string_end 20 "$fixed_squashfs_name")"
-    for file in f4 f5 ; do
-      if [ -r "${BUILD_OUTPUT}/boot/isolinux/${file}" ] ; then
-        sed -i "s/%SQUASHFS_NAME%/${fixed_squashfs_name}/" "${BUILD_OUTPUT}/boot/isolinux/${file}"
-        sed -i "s/%SQUASHFS_NAME%/${fixed_squashfs_name}/" "${BUILD_OUTPUT}/boot/isolinux/${file}"
-      fi
-    done
-
     # generate addon list
     rm -f "${BUILD_OUTPUT}/${ADDONS_LIST_FILE}"
     for name in "${BUILD_OUTPUT}"/boot/isolinux/addon_*.cfg ; do