python: Add DVPlan build system

DVPlan is not available yet, but pre-emptively add an entry here to the
nix pyproject overrides to allow us to eventually get DVPlan via nix.

Signed-off-by: Alex Jones <[email protected]>

Author: AlexJones0

lib/pyprojectOverrides.nix

@@ -29,6 +29,7 @@
     cssselect.setuptools = [];
     cssutils.setuptools = [];
     cython.setuptools = [];
+    dvplan.hatchling = [];
     dvsim.hatchling = [];
     edalize.setuptools = [];
     enlighten.setuptools = [];