installer: remove temporary pkgs from target after copying live image.

installer.sh.in

@@ -779,6 +779,8 @@ ${BOLD}Do you want to continue?${RESET}" 20 80 || return
         chroot $TARGETDIR userdel -r $USERNAME >>$LOG 2>&1
         echo "Rebuilding initramfs for target ..." >$LOG
         chroot $TARGETDIR dracut --force >>$LOG 2>&1
+        echo "Removing unused packages from target ..." >$LOG
+        xbps-remove -r $TARGETDIR -Ry dialog f2fs-tools >>$LOG 2>&1
     else
         # network install, use packages.
         install_packages