acpi/tpm: Gracefully handle missing TPM module.

When TPM support is enabled, verify the TPM_DID_VID field is not
all zeroes or all ones before returning 0xf in the _STA method.

This avoids these kernel errors when no module is installed:
[    3.426426] tpm_tis 00:01: tpm_transmit: tpm_send: error -5
[    3.432049] tpm_tis: probe of 00:01 failed with error -5

Change-Id: Ia089d4232e0986b3bc635d346e68d982e8aecd44
Signed-off-by: Tobias Diedrich <ranma+coreboot@tdiedrich.de>
Reviewed-on: https://review.coreboot.org/13713
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Duncan Laurie <dlaurie@google.com>

0 files changed, 0 insertions, 0 deletions