Adding commands for OTP authentication of uLoader.

Signing of the uLoader images is disabled by default. To
enable, you have to edit tools/ImageGenerator/uldr_gen.sh,
and replace:
  done < hdr_gen_cfg --> done < secure_hdr_gen_cfg

You also obviously have to set up the OTP with the key
information.

Change-Id: Ieb85e51946728957a4b4a88881f197adaeb44a92
7 files changed