QCssParser: remove 239 unneeded relocations

Same change as in QColor (d38f86e50b).

  relocs: -239
  text:  +2248B
  data:  -3872B

(optimized GCC 6.1 Linux AMD64 build). The text size increase means
we pushed the data into an immutable section.

Change-Id: Iad10c877d4a4877878dded56a7ef1e14ff92c996
Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com>

src/gui/text/qcssparser.cpp

@@ -54,7 +54,7 @@ using namespace QCss;
 
 struct QCssKnownValue
 {
-    const char *name;
+    const char name[28];
     quint64 id;
 };