tpm: selftest: cleanup after unseal with wrong auth/policy test

Unseal with wrong auth or wrong policy test affects DA lockout
and eventually causes the tests to fail with:
"ProtocolError: TPM_RC_LOCKOUT: rc=0x00000921"
when the tests run multiple times.
Send tpm clear command after the test to reset the DA counters.

Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>