message: fix error in blob2cpp when using Python 3
diff: import os
  import sys
  import argparse
  +from array import array
  # Generates a C++ file from the specified binary blob
  def generate(in_path, out_path, namespace):
  @@ -41,7 +42,7 @@ def generate(in_path, out_path, namespace):
  out_file.write('\n')
  # Read the file
  - in_data = in_file.read()
  + in_data = array('B', in_file.read())
  # Write the size
  out_file.write('const size_t %s_size = %d;\n\n' % (var_name, len(in_data)))
  @@ -49,7 +50,7 @@ def generate(in_path, out_path, namespace):
  # Write the data
  out_file.write('unsigned char %s[] = {' % var_name)
  for i in range(len(in_data)):
  - c = ord(in_data[i])
  + c = in_data[i]
  if i > 0:
  out_file.write(',')
  if (i+1) % 20 == 1:
  