Move gRPC/Protobuf logs handling to a dedicated file.

(cherry picked from commit b54c65005a)

src/ngx.hpp

@@ -0,0 +1,7 @@
+#pragma once
+
+extern "C" {
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_http.h>
+}