fix: block while waiting for UART data

internal/serialport/serial_linux.go

@@ -8,7 +8,7 @@ import (
 )
 
 func Open115200(path string) (*os.File, error) {
-	file, err := os.OpenFile(path, os.O_RDWR|unix.O_NOCTTY|unix.O_NONBLOCK, 0)
+	file, err := os.OpenFile(path, os.O_RDWR|unix.O_NOCTTY, 0)
 	if err != nil {
 		return nil, err
 	}