APM support forwarding: Add new host to appSettings:

This new host is different to the standard mavlink forwarding
one because it is meant to get disconnected when QGC closes
so the users don't leave by mistake the connection to the
support servers opened

src/Settings/App.SettingsGroup.json

@@ -325,6 +325,13 @@
     "longDesc":  "Host name to forward mavlink to. i.e: localhost:14445",
     "type":             "string",
     "default":     "localhost:14445"
+},
+{
+    "name":      "forwardMavlinkAPMSupportHostName",
+    "shortDesc": "Ardupilot Support Host name",
+    "longDesc":  "Ardupilot Support server to forward mavlink to. i.e: support.ardupilot.org:xxxx",
+    "type":      "string",
+    "default":   "support.ardupilot.org:xxxx"
 }
 ]
 }

src/Settings/AppSettings.cc

@@ -149,6 +149,7 @@ DECLARE_SETTINGSFACT(AppSettings, saveCsvTelemetry)
 DECLARE_SETTINGSFACT(AppSettings, firstRunPromptIdsShown)
 DECLARE_SETTINGSFACT(AppSettings, forwardMavlink)
 DECLARE_SETTINGSFACT(AppSettings, forwardMavlinkHostName)
+DECLARE_SETTINGSFACT(AppSettings, forwardMavlinkAPMSupportHostName)
 
 DECLARE_SETTINGSFACT_NO_FUNC(AppSettings, indoorPalette)
 {

src/Settings/AppSettings.h

@@ -65,6 +65,7 @@ public:
     DEFINE_SETTINGFACT(firstRunPromptIdsShown)
     DEFINE_SETTINGFACT(forwardMavlink)
     DEFINE_SETTINGFACT(forwardMavlinkHostName)
+    DEFINE_SETTINGFACT(forwardMavlinkAPMSupportHostName)
 
 
     // Although this is a global setting it only affects ArduPilot vehicle since PX4 automatically starts the stream from the vehicle side