dsdb-acl: Re-indent acl_add_privileges() by using an early return

Change-Id: I26bf7347ea376095fd98c4622abd57a2d2c6ff86
Signed-off-by: Andrew Bartlett <abartlet@samba.org>
dsdb-tests: Add tests for dNSHostName and ServicePrincipalName attributes

To the machine account privilege tests.

Signed-off-by: Samuel Cabrero <samuelcabrero@kernevil.me>
s4-acl: Use message sAMAccountName if exists in Validated-SPN validated write

If the modify ldb message contains the samAccountName element, use it to
compute the SPN restrictions instead the element value in the SAM database.

Signed-off-by: Samuel Cabrero <samuelcabrero@kernevil.me>
s4-acl: Use message sAMAccountName if exists in Validated-DNS-Host-Name

If the modify ldb message contains the samAccountName element, use it to
compute the dnsHostName restrictions instead the element value in the SAM
database.

Signed-off-by: Samuel Cabrero <samuelcabrero@kernevil.me>