tpm: Handle unimplemented TIS_REG_IFACE_ID in tis_get_tpm_version()

tpm: Handle unimplemented TIS_REG_IFACE_ID in tis_get_tpm_version()

If a device reports 0xf in the InterfaceType field of the TPM_INTERFACE_ID,
then the rest of the fields are invalid, and the InterfaceVersion field of
the TPM_INTF_CAPABILITY register must be checked instead.

Signed-off-by: Stephen Douthit <stephend@silicom-usa.com>
Tested-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com>