Remove not implemented logging from OSCPUOperation

This is the correct implementation.

Change-Id: Ic700a079f993a92c7e60ede7bd14320da1321bfc
diff --git a/services/server/env/fuchsia/osfunc_platform.cc b/services/server/env/fuchsia/osfunc_platform.cc
index 3104800..0099433 100644
--- a/services/server/env/fuchsia/osfunc_platform.cc
+++ b/services/server/env/fuchsia/osfunc_platform.cc
@@ -50,7 +50,8 @@
 PVRSRV_ERROR
 OSCPUOperation(PVRSRV_CACHE_OP uiCacheOp)
 {
-	NOT_IMPLEMENTED();
+	// Zircon doesn't support doing a global cache flush. If this returns not
+	// supported, the client can handle flushing individual cache lines.
 	return PVRSRV_ERROR_NOT_SUPPORTED;
 }