pd replaced by constraints file only
Created by: Silabs-ArjanB
Removed 'pd' dir since we now have 'constraints' dir with sdc file.
@davideschiavone
I will close https://github.com/openhwgroup/cv32e40p/pull/273 and https://github.com/openhwgroup/cv32e40p/pull/305 as well unless you indicate a good reason to keep those.
Signed-off-by: Arjan Bink Arjan.Bink@silabs.com