This actually came up a few weeks ago - there's no way to filter outbound
ICMP for "broadcast addresses", because what defines a broadcast address
depends on the subnetting at the receiving end. For example, 10.1.1.119
may be a host on 10.1.1.0/24, or a broadcast on 10.1.1.112/29.
"no ip directed-broadcast" drops all IP destined for the broadcast address
_on an interface_, AFAIK.