libcli/security: begin claim_v1_check_and_sort with Boolean checks

libcli/security: begin claim_v1_check_and_sort with Boolean checks

claim_v1_check_and_sort() is meant to sort the claim values and check
that there are no duplicates, as well as making some value checks.

In order to ease into the idea, we look first at the case where the claim
has Boolean values. There are only two values allowed, which limits the
length of a valid claim set and means we only really need to "sort" in
the {1, 0} case, which we rewrite in place as {0, 1}.

That's what will happen with other types: we'll sort in-place, make
some checks on values, set flags, and return an error if there are
duplicates or value errors.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>