MavLinkProtocol: Fix constructor warnings

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

src/comm/MAVLinkProtocol.cc

@@ -53,6 +53,8 @@ const char* MAVLinkProtocol::_logFileExtension = "mavlink";             ///< Ext
 MAVLinkProtocol::MAVLinkProtocol(QGCApplication* app, QGCToolbox* toolbox)
     : QGCTool(app, toolbox)
     , m_enable_version_check(true)
+    , _message({})
+    , _status({})
     , versionMismatchIgnore(false)
     , systemId(255)
     , _current_version(100)

src/comm/MAVLinkProtocol.h

@@ -108,8 +108,8 @@ protected:
     uint64_t    totalLossCounter[MAVLINK_COMM_NUM_BUFFERS];     ///< Total messages lost during transmission.
     float       runningLossPercent[MAVLINK_COMM_NUM_BUFFERS];   ///< Loss rate
 
-    mavlink_message_t _message = {};
-    mavlink_status_t _status   = {};
+    mavlink_message_t _message;
+    mavlink_status_t _status;
 
     bool        versionMismatchIgnore;
     int         systemId;