Fix bug (and add test) for a function-like-macro appearing as a non-macro.

That is, when a function-like macro appears in the content without
parentheses it should be accepted and passed on through, (previously
the parser was regarding this as a syntax error).
diff --git a/glcpp-parse.y b/glcpp-parse.y
index 16d2a28..6f158d9 100644
--- a/glcpp-parse.y
+++ b/glcpp-parse.y
@@ -133,6 +133,10 @@
 		printf ("%s", $1);
 		talloc_free ($1);
 	}
+|	FUNC_MACRO {
+		printf ("%s", $1);
+		talloc_free ($1);
+	}
 |	macro {
 		_print_string_list ($1);
 	}