Simplify variant in ls_

Change-Id: I2bccf7b171f0bae619e935edba5a157a2398d877
diff --git a/src/grammars.hpp b/src/grammars.hpp
index dfb8c10..ae7a980 100644
--- a/src/grammars.hpp
+++ b/src/grammars.hpp
@@ -47,7 +47,7 @@
 } const ls_options;
 
 auto const ls_def =
-    ls_::name >> *(space_separator >> ls_options) >> -(space_separator >> ((dataPathListEnd | dataPath | schemaPath) | (module >> "*")));
+    ls_::name >> *(space_separator >> ls_options) >> -(space_separator >> (dataPathListEnd | dataPath | schemaPath | (module >> "*")));
 
 auto const cd_def =
     cd_::name >> space_separator > dataPath;