tpm2-tss: bump to version 2.1.0

tpm2-tss: bump to version 2.1.0

- Drop C++ requirement (tmp2-tss is pure C now).
- Add explicit dependency on openssl (gnutls can be used too but this
  option will be added by a subsequent patch).
- Drop the patch on tcti_socket.cpp, which is not applicable.
- Add a patch already submitted upstream to support using libressl[1].
- Update LICENSE hash. The terms are is still BSD-2-Clause but the file
  now contains a SPDX license identifier.

1. https://github.com/tpm2-software/tpm2-tss/pull/1207

Signed-off-by: Carlos Santos <casantos@datacom.com.br>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>