If two imported targets in different directories have the same name we
should still be able to propagate transitive usage requirements from
both. Fix the DAG checker to work with target pointers instead of
target names since the pointers will not be duplicated even if the names
are.
Fixes: #18345
If two imported targets in different directories have the same name we
should still be able to propagate transitive link dependencies from
both. Fix the target and link dependency analyzers to de-duplicate
targets using target pointers rather than target names since the
pointers will not be duplicated even if the names are.
Issue: #18345