install.sh: Create all destination directories

The explit list of destination directories to create is incomplete which
becomes apperent, if installed into a empty directoy with DESTDIR=...

Create any required directory implicitly.

install.sh

@@ -58,14 +58,15 @@ function install_if()
     shift 2
 
     if need_update "$src" "$dst"; then
+	dir="$(dirname "$dst")"
+	test -d "$dir" || mkdir -p "$dir"
         "$@" "$src" "$dst"
     fi
     return 0
 }
 
 function install_desktop_file()
 {
-    test -d ${desktopdir} || mkdir -p ${desktopdir}
     install_if "$1" "$2" $INSTALL_DATA
     update-desktop-database ${desktopdir}
 }
@@ -94,13 +95,6 @@ function install_symlink()
 
 umask 022;
 
-mkdir -p "$DESTDIR$usr_bindir"
-mkdir -p "$DESTDIR$usr_sbindir"
-mkdir -p "$DESTDIR$systemdunitdir"
-mkdir -p "$DESTDIR$usrlocal_bindir"
-mkdir -p "$DESTDIR$udev_rulesdir"
-mkdir -p "$DESTDIR$udev_helperdir"
-
 install_exec make-automaps/make-automaps                 "$DESTDIR$usr_sbindir/make-automaps"
 install_data misc_systemd_units/automount.service        "$DESTDIR$systemdunitdir/automount.service"
 install_data misc_systemd_units/dhcrelay.service         "$DESTDIR$systemdunitdir/dhcrelay.service"