s3:modules:full_audit - avoid log spam

PR: https://github.com/freenas/ports/pull/941

Due to continuing work on Samba's VFS, some operations have changed
name. For example unlink -> unlinkat, mkdir -> mkdirat. The original
design of vfs_full_audit was to log all vfs operations if it
encountered one that was not in its lookup table for ops. This results in
a massive increase in the amount of logging being generated.

This commit expands the lookup table to include an `oldname` string that
the user's configuration can be checked against so that the old name,
e.g. `unlink`, will continue to log the appropriate VFS operation without
configuration change. In the case of totally unknown parameters, deny access
to the share with a log message that auditing is significantly misconfigured.
The reasoning for this is that auditing failure is a significant error and
users should not be granted access until it is resolved.