swtpm: Implement CMD_LOCK_STORAGE to lock storage

Implement CMD_LOCK_STORAGE / PTM_LOCK_STORAGE for a user to be able to
lock the storage of the storage backend (if supported) after its lock
has been released for example when the 'savestate' blob was received
while the TPM state was migrated.

Also adjust test case and extend man pages.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
9 files changed