http2: pass session to DEBUG_HTTP2SESSION2

When configure with --debug-http2 --debug-nghttp2 the following
compilation error is generated:

DEBUG_HTTP2SESSION2(this, "fatal error receiving data: %d", ret);
                          ^
../src/node_http2.cc:1690:27:
error: invalid use of 'this' outside of a non-static member function

1 errors generated.

OnStreamReadImpl is static and I think the intention was to pass in the
session variable here.

PR-URL: #20815
Refs: #20806
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>

src/node_http2.cc

@@ -1691,7 +1691,7 @@ void Http2Session::OnStreamReadImpl(ssize_t nread,
     // ssize_t to int. Cast here so that the < 0 check actually works on
     // Windows.
     if (static_cast<int>(ret) < 0) {
-      DEBUG_HTTP2SESSION2(this, "fatal error receiving data: %d", ret);
+      DEBUG_HTTP2SESSION2(session, "fatal error receiving data: %d", ret);
 
       Local<Value> argv[1] = {
         Integer::New(isolate, ret),