ArduCopter: Fix use of logical op instead of bitwise op

../../ArduCopter/GCS_Mavlink.cpp: In member function 'void Copter::send_extended_status1(mavlink_channel_t)':
../../ArduCopter/GCS_Mavlink.cpp:281:37: error: suggest parentheses around operand of '!' or change '&' to '&&' or '!' to '~' [-Werror=parentheses]
     uint32_t sensors_error_flags = !control_sensors_health & control_sensors_enabled & control_sensors_present;
                                     ^
compilation terminated due to -Wfatal-errors.
cc1plus: all warnings being treated as errors

Thanks to Ralph Campbell <ralphcampbell1@gmail.com> for the bug report.

ArduCopter/GCS_Mavlink.cpp

@@ -278,7 +278,7 @@ NOINLINE void Copter::send_extended_status1(mavlink_channel_t chan)
 
 #if FRSKY_TELEM_ENABLED == ENABLED
     // give mask of error flags to Frsky_Telemetry
-    uint32_t sensors_error_flags = !control_sensors_health & control_sensors_enabled & control_sensors_present;
+    uint32_t sensors_error_flags = (~control_sensors_health) & control_sensors_enabled & control_sensors_present;
     frsky_telemetry.update_sensor_status_flags(sensors_error_flags);
 #endif