TT#41500 Run dpkg-reconfigure tzdata to workaround a bug in grml-debootstrap

Currently grml-debootstrap only sets /etc/localtime, but not
/etc/timezone, so this confuses the system with libraries/tools
that read the former and others the latter. Reconfigure tzdata so
that it can get both files into a consistent state.

Change-Id: Id34c1a088809fbac19957a750c31fb8f3ceda893
(cherry picked from commit d5df0c0f84)
(cherry picked from commit 33d5cc6587)

templates/scripts/includes/deployment.sh

@@ -1288,6 +1288,9 @@ save
 EOT
 fi
 
+# TT#41500: Make sure the timezone setup is coherent
+grml-chroot "$TARGET" dpkg-reconfigure --frontend=noninteractive tzdata
+
 # provide useable swap partition
 echo "Enabling swap partition $SWAP_PARTITION via /etc/fstab"
 cat >> "${TARGET}/etc/fstab" << EOF