Make sure ${exportdir} for stable-new exists.

config/debian/common

@@ -61,6 +61,7 @@ function punew_do() {
 
     local exportdir="${qdir}/tree/${STAMP}"
     local targetdir="${qdir}/export"
+    mkdir -p -- ${exportdir}
     dak export -q "${queue}" -d "${exportdir}" --all
     ln -sfT ${exportdir} ${targetdir}
     find "${qdir}/tree" -mindepth 1 -maxdepth 1 -not -name "${STAMP}" -type d -print0 | xargs --no-run-if-empty -0 rm -rf