tools: Ignore newlines in libvirt-guests.sh guest list

The list file expects all guest UUIDs on the same line as the URI
which the guests run on. This does not happen when the list is
echo'ed in quotes. When stripping the quotes, newlines get transformed
into spaces. Without this, only the first guest on the list is actually
handled.

Based on a fix by Omar Siam <simar@gmx.net>

Bug-Ubuntu: http://bugs.launchpad.net/bugs/1591695

Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

tools/libvirt-guests.sh.in

@@ -499,7 +499,7 @@ stop() {
         fi
 
         if [ -n "$list" ]; then
-            echo "$uri" "$list" >>"$LISTFILE"
+            echo "$uri" $list >>"$LISTFILE"
         fi
     done
     set +f