win build: rm win_inet_pton

was needed by PySocks; and we no longer use PySocks
also, it seems the functionality it provided is now part of Python stdlib since 3.4
https://docs.python.org/3/library/socket.html#socket.inet_pton

related: #2358

contrib/build-wine/prepare-wine.sh

@@ -112,8 +112,6 @@ done
 # upgrade pip
 $PYTHON -m pip install pip --upgrade
 
-# install PySocks
-$PYTHON -m pip install win_inet_pton==1.0.1
 
 $PYTHON -m pip install -r $here/../deterministic-build/requirements-binaries.txt