event/Thread, ...: fix printf->libfmt remains

src/input/Init.cxx

@@ -71,12 +71,12 @@ input_stream_global_init(const ConfigData &config, EventLoop &event_loop)
 			input_plugins_enabled[i] = true;
 		} catch (const PluginUnconfigured &e) {
 			FmtDebug(input_domain,
-				 "Input plugin '{}' is not configured: %s",
+				 "Input plugin '{}' is not configured: {}",
 				 plugin->name, e.what());
 			continue;
 		} catch (const PluginUnavailable &e) {
 			FmtDebug(input_domain,
-				 "Input plugin '{}' is unavailable: %s",
+				 "Input plugin '{}' is unavailable: {}",
 				 plugin->name, e.what());
 			continue;
 		} catch (...) {