selftests: tpm2: remove redundant ord()

When testing with FLAG_DEBUG enabled client, it emits the following
error messages:

File "/root/tpm2/tpm2.py", line 347, in hex_dump
    d = [format(ord(x), '02x') for x in d]
File "/root/tpm2/tpm2.py", line 347, in <listcomp>
    d = [format(ord(x), '02x') for x in d]
TypeError: ord() expected string of length 1, but int found

The input of hex_dump() should be packed binary data.  Remove the
ord().

Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>