[MEDIUM] acl: when possible, report the name and requirements of ACLs in warnings

[MEDIUM] acl: when possible, report the name and requirements of ACLs in warnings

When an ACL is referenced at a wrong place (eg: response during request, layer7
during layer4), try to indicate precisely the name and requirements of this ACL.

Only the first faulty ACL is returned. A small change consisting in iterating
that way may improve reports :
   cap = ACL_USE_any_unexpected
   while ((acl=cond_find_require(cond, cap))) {
     warning()
     cap &= ~acl->requires;
   }

This will report the first ACL of each unsupported type. But doing so will
mangle the error reporting a lot, so we need to rework error reports first.