Fix index underflow causing segfault on DPI change (#241)

* Fix index underflow causing segfault on DPI change

* Stop over-allocating sensor lists

src/logid/features/DPI.cpp

@@ -103,9 +103,10 @@ void DPI::setDPI(uint16_t dpi, uint8_t sensor)
     hidpp20::AdjustableDPI::SensorDPIList dpi_list;
     if(_dpi_lists.size() <= sensor) {
         dpi_list = _adjustable_dpi->getSensorDPIList(sensor);
-        for(std::size_t i = _dpi_lists.size()-1; i <= sensor; i++) {
+        for(std::size_t i = _dpi_lists.size(); i < sensor; i++) {
             _dpi_lists.push_back(_adjustable_dpi->getSensorDPIList(i));
         }
+        _dpi_lists.push_back(dpi_list);
     }
     dpi_list = _dpi_lists[sensor];
     _adjustable_dpi->setSensorDPI(sensor, getClosestDPI(dpi_list, dpi));