Enable glyph cache workaround for GC2000 as well

The glyph cache resize is clearly doing something that is not actually
legal with OpenGL ES. Until this gets investigated properly, add the
Vivante GC2000 (found in the commonly used i.MX6 quad) to the list since
reports show that the issue occurs there as well.

Task-number: QTBUG-49490
Change-Id: Ia890346d8dbb1691bc113e2ef522713ba6709393
Reviewed-by: Louis Kröger <louis.kroeger@gmail.com>
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>

src/gui/kernel/qopenglcontext.cpp

@@ -1008,6 +1008,7 @@ bool QOpenGLContext::makeCurrent(QSurface *surface)
                             || qstrncmp(rendererString, "Adreno 4xx", 8) == 0 // Same as above but without the '(TM)'
                             || qstrcmp(rendererString, "GC800 core") == 0
                             || qstrcmp(rendererString, "GC1000 core") == 0
+                            || strstr(rendererString, "GC2000") != 0
                             || qstrcmp(rendererString, "Immersion.16") == 0;
             }
             needsWorkaroundSet = true;