Move nullptr check to modefilter

wfmain.cpp

@@ -2233,11 +2233,6 @@ void wfmain::doCmd(commandtype cmddata)
     std::shared_ptr<void> data = cmddata.data;
     // This switch is for commands with parameters.
     // the "default" for non-parameter commands is to call doCmd(cmd).
-    if (data == nullptr)
-    {
-        qInfo(logSystem()) << __PRETTY_FUNCTION__ << "WARNING: data is null";
-        return;
-    }
 
     switch (cmd)
     {
@@ -2255,8 +2250,14 @@ void wfmain::doCmd(commandtype cmddata)
         }
         case cmdSetModeFilter:
         {
-            mode_info m = (*std::static_pointer_cast<mode_info>(data));
-            emit setMode(m);
+            if (data == nullptr)
+            {
+                qInfo(logSystem()) << __PRETTY_FUNCTION__ << "WARNING: data is null";
+            }
+            else {
+                mode_info m = (*std::static_pointer_cast<mode_info>(data));
+                emit setMode(m);
+            }
             break;
         }
         case cmdSetTxPower: