Tests: Re-enable style param for testdivision.

My earlier commit (cfcfa3f0) removed the use of style parameter.
This commit adds it back.

Ticket: #2987 (GCC: warning: unused parameter ‘style’ in test/testdivision.cpp:39:10)

test/testdivision.cpp

@@ -42,7 +42,8 @@ private:
         errout.str("");
 
         Settings settings;
-        settings.addEnabled("style");
+        if (style)
+            settings.addEnabled("style");
 
         // Tokenize..
         Tokenizer tokenizer(&settings, this);