MAJOR: acl: remove the arg_mask from the ACL definition and use the sample fetch's

MAJOR: acl: remove the arg_mask from the ACL definition and use the sample fetch's

Now that ACLs solely rely on sample fetch functions, make them use the
same arg mask. All inconsistencies have been fixed separately prior to
this patch, so this patch almost only adds a new pointer indirection
and removes all references to ARG*() in the definitions.

The parsing is still performed by the ACL code though.