s3:auth: Tidy up some of the API confusion in create_token_from_XXX() calls.

s3:auth: Tidy up some of the API confusion in create_token_from_XXX() calls.

Based on Michaels example, split out the return of NT_STATUS_NO_MEMORY
on talloc fail from other possible errors. Allow the NTSTATUS return
to be the only valid indication of success in these calls.

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Michael Adam <obnox@samba.org>
Reviewed-by: Andreas Schneider <asn@samba.org>
Autobuild-User(master): Andreas Schneider <asn@cryptomilk.org>
Autobuild-Date(master): Tue Dec 11 20:04:25 CET 2012 on sn-devel-104