The spi tis_sendrecv() implementation was always returning success
for all transactions. Correct this by returning -1 on error when
tpm2_process_command() returns 0 since that's its current failure
return code.
BUG=b:36598499
Change-Id: I8bfb5a09198ae4c293330e770271773a185d5061
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/19058
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins)