Don't try to re-read partition table when building VMs using loop devices

This always causes "BLKRRPART: Invalid argument", so there's probably
no point in executing this at all.

Fixes #38 @ github

diff --git a/grml-debootstrap b/grml-debootstrap
index dba6434..02498cc 100755 (executable)
--- a/grml-debootstrap
+++ b/grml-debootstrap
@@ -1121,8 +1121,6 @@ prepare_vm() {
   LOOP_PART="$(echo "${DEVINFO##add map }" | sed 's/ .*//')" # 'loop1p1'
   export TARGET="/dev/mapper/$LOOP_PART" # '/dev/mapper/loop1p1'
 
-  blockdev --rereadpt "${LOOP}"
-
   if [ -z "$TARGET" ] ; then
      eerror "Error: target could not be set to according /dev/mapper/* device." ; eend 1
      bailout 1