ota_update: read password invisibly

scripts/ota_update.py

@@ -5,6 +5,9 @@ import socket
 import struct
 import hashlib
 import os
+import time
+
+from getpass import getpass
 
 def readMessage(sock):
     data = sock.recv(4)
@@ -28,7 +31,7 @@ with open("../data/etc/auth", "r") as authFile:
 _, host, port, filename = sys.argv
 
 # read and store the password from the user
-pwd = input("Enter password: ")
+pwd = getpass()
 
 s = socket.create_connection( (host, int(port)) )