SyntaxHighligher: Remove the need to specify format for spaces

It has all means to know itself.

Change-Id: I464c195c5ee47e5fc58414a280c166e4a332c588
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/qmakeprojectmanager/profilehighlighter.cpp

@@ -99,7 +99,7 @@ void ProFileHighlighter::highlightBlock(const QString &text)
             break;
     }
 
-    applyFormatToSpaces(text, formatForCategory(ProfileVisualWhitespaceFormat));
+    formatSpaces(text);
 }
 
 } // namespace Internal