fixed --add option handling

dracut-functions

@@ -257,8 +257,9 @@ check_modules() {
 	[[ $dracutmodules != all ]] && ! strstr "$dracutmodules" "$mod" && \
 	    continue
 	strstr "$omit_dracutmodules" "$mod" && continue
-	strstr "$add_dracutmodules" " $mod " \
-	    || should_source_module "$moddir" || continue
+	if ! strstr "$add_dracutmodules" " $mod "; then
+	    should_source_module "$moddir" || continue
+        fi
 	mods_to_load+=" $mod "
     done
 }