neutrino: speed up the fontrenderer

Speed up the fontrenderer by *not* using the GXA accelerator. To
prevent artifacts, add a routine to framebuffer class to sync on
the GXA engine being ready with drawing.

git-svn-id: file:///home/bas/coolstream_public_svn/THIRDPARTY/applications/neutrino-experimental@196 e54a6e83-5905-42d5-8d5c-058d10e6a962

src/driver/framebuffer.h

@@ -214,6 +214,12 @@ class CFrameBuffer
 		bool Lock(void);
 		void Unlock(void);
 		bool Locked(void) { return locked; };
+#ifdef USE_NEVIS_GXA
+		void add_gxa_sync_marker(void);
+		void waitForIdle(void);
+#else
+		inline void waitForIdle(void) {};
+#endif
 };