tpm: Perform hashing separately from logging

tpm: Perform hashing separately from logging

Instead of calculating the hash in hash_log_event(), create a new
function (tpm_fill_hash) that will create the hash, and update all
callers to use tpm_fill_hash() before calling hash_log_event().  This
reduce the number of parameters to hash_log_event().

Rename hash_log_event() and hash_log_extent_event() to tpm_log_event()
and tpm_log_extend_event() now that these functions no longer
implement the hashing.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>