This fixes the following compiler warning when building for Windows:
mingw/device.c: In function ‘setup_device’:
mingw/device.c:92:9: error: unused variable ‘thread’ [-Werror=unused-variable]
HANDLE thread;
^
bool found = false;
int err;
bool found = false;
int err;
get_config_string(lookup_config(config_tree, "Device"), &device);
get_config_string(lookup_config(config_tree, "Interface"), &iface);
get_config_string(lookup_config(config_tree, "Device"), &device);
get_config_string(lookup_config(config_tree, "Interface"), &iface);