gsctool: support for enabling/disabling TPM.

This patch introduces '-m' or '--tpm_mode' flag, which either
enables or disables TPM.

(chroot) gsctool -m enable
open_device 18d1:5014
found interface 3 endpoint 4, chunk_len 64
READY
-------

(chroot) gsctool --tpm_mode disable
open_device 18d1:5014
found interface 3 endpoint 4, chunk_len 64
READY
-------

BUG=b:77543596
BRANCH=gsctool
TEST=manually

Signed-off-by: Namyoon Woo <namyoon@google.com>

Change-Id: I2feb8c51d4343a49f2f5d43291c304e3ad140057
Reviewed-on: https://chromium-review.googlesource.com/1106295
Commit-Ready: Namyoon Woo <namyoon@chromium.org>
Tested-by: Namyoon Woo <namyoon@chromium.org>
Reviewed-by: Namyoon Woo <namyoon@chromium.org>
2 files changed