Abort early in installer_preseed if d-i is not included on the image (Closes: #745855).

scripts/build/installer_preseed

@@ -24,6 +24,14 @@ Arguments "${@}"
 Read_conffiles config/all config/common config/bootstrap config/chroot config/binary config/source
 Set_defaults
 
+
+# Check d-i configuration
+case "${LB_DEBIAN_INSTALLER}" in
+	false)
+		exit 0
+		;;
+esac
+
 Echo_message "Begin including local preseeds..."
 
 # Checking stage file