fix some compiler warnings

[vindolin]

Fix for the following warnings:

.\RemoteDebug\src\RemoteDebug.cpp: In member function 'void RemoteDebug::processCommand()':
.\RemoteDebug\src\RemoteDebug.cpp:1520:39: warning: format '%lu' expects argument of type 'long unsigned int', but argument 3 has type 'uint32_t {aka unsigned int}' [-Wformat=]
   DebugWS.printf("$app:M:%lu:\n", free);
                                       ^
.\RemoteDebug\src\RemoteDebug.cpp: In member function 'void RemoteDebug::wsSendInfo()':
.\RemoteDebug\src\RemoteDebug.cpp:1931:117: warning: format '%lu' expects argument of type 'long unsigned int', but argument 6 has type 'uint32_t {aka unsigned int}' [-Wformat=]
   DebugWS.printf("$app:V:%s:%s:%c:%lu:%c:N\n", version.c_str(), board.c_str(), features, getFreeMemory(), dbgEnabled);
                                                                                                                     ^
.\RemoteDebug\src\RemoteDebugWS.cpp: In function 'void webSocketEvent(uint8_t, WStype_t, uint8_t*, size_t)':
.\RemoteDebug\src\RemoteDebugWS.cpp:233:6: warning: unused variable 'blk_count' [-Wunused-variable]
  int blk_count = 0;
      ^
.\RemoteDebug\src\RemoteDebugWS.cpp:234:7: warning: unused variable 'ipaddr' [-Wunused-variable]
  char ipaddr[26];
       ^