s3-privs Rework access_check_object() to take two privileges

s3-privs Rework access_check_object() to take two privileges

This allows the privileges bitmap to be used only when setting
privileges, and uses an the LUID constant for all 'does this user
have this privilege' operations.

The advantage is that we now only need one API to determine if a
token has a privilege, and much less code needs to know what type
is used for the underlying bitmap.

Andrew Bartlett

Signed-off-by: Andrew Tridgell <tridge@samba.org>