Since Linux 5.6 tpm_version_major sysfs file is avaialble which gives
the TPM version.

Using this file the test can be skipped on systems with TPM 1.2.
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>