File gr-limesdr-3-no-return-from-nonvoid-function.patch of Package gr-limesdr

diff -up gr-limesdr/lib/device_handler.cc.xxxx gr-limesdr/lib/device_handler.cc
--- gr-limesdr/lib/device_handler.cc.xxxx	2019-10-20 09:30:50.192229903 +0200
+++ gr-limesdr/lib/device_handler.cc	2019-10-20 10:21:14.900708306 +0200
@@ -366,6 +366,7 @@ device_handler::set_rf_freq(int device_n
             << "ERROR: device_handler::set_rf_freq(): rf_freq must be more than 0 Hz."
             << std::endl;
         close_all_devices();
+        return 0;
     } else {
         std::cout << "INFO: device_handler::set_rf_freq(): ";
         if (LMS_SetLOFrequency(device_handler::getInstance().get_device(device_number),
@@ -472,6 +473,7 @@ double device_handler::set_analog_filter
                   << std::endl;
         close_all_devices();
     }
+    return 0;
 }
 
 double device_handler::set_digital_filter(int device_number,
@@ -508,6 +510,7 @@ double device_handler::set_digital_filte
             << std::endl;
         close_all_devices();
     }
+    return 0;
 }
 
 unsigned
@@ -537,6 +540,7 @@ device_handler::set_gain(int device_numb
                "range [0, 60]."
             << std::endl;
         close_all_devices();
+        return 0;
     }
 }