dirstate: Pass the final DirstateItem to _rustmap.addfile()...
dirstate: Pass the final DirstateItem to _rustmap.addfile()
Now that the Python DirstateItem class wraps a Rust DirstateEntry value,
use that value directly instead of converting through v1 data + 5 booleans.
Also remove propogating the return value. None of the callers look at it,
and it is always None.
Differential Revision:
https://phab.mercurial-scm.org/D11494
