libadmin: add support for UAE error translation

libadmin: add support for UAE error translation

Routine util_AdminErrorCodeTranslate() provides the support for error
translation that is used by the libadmin package and several Windows utilities,
including the Windows implementation of translate_et (translate_et_nt.c).

Enhance it so the Windows translate_et can translate UAE errors.
No changes are required for translate_et_nt.c.

Note: this may be unit-tested under Unix via a libadmin test:
$ src/libadmin/test/afscp UtilErrorTranslate -error 49733388
49733388 -> Permission denied

Change-Id: Iee85e09813e3488558c0f1c6682d0049b912abc7
Reviewed-on: https://gerrit.openafs.org/14648
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>