vtpm: Correct timeout units and command duration

vtpm: Correct timeout units and command duration

Add two patches:
vtpm-microsecond-duration.patch fixes the units for timeouts and command
durations.
vtpm-command-duration.patch increases the timeout linux uses to allow
commands to succeed.

Linux works around low timeouts, but not low durations.  The second
patch allows commands to complete that often timeout with the lower
command durations.

Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Reviewed-by: Daniel P. Smith <dpsmith@apertussolutions.com>