Allow picking up include/lib dirs from CFLAGS/LDFLAGS for Windows targets

In cpython-mingw-3.10, this was part of a patch named "allow static
tcltk".

Co-authored-by: Алексей <[email protected]>

Author: 2 people

setup.py

@@ -925,7 +925,7 @@ def init_inc_lib_dirs(self):
         if HOST_PLATFORM == 'hp-ux11':
             self.lib_dirs += ['/usr/lib/hpux64', '/usr/lib/hpux32']
 
-        if MACOS:
+        if MACOS or MS_WINDOWS:
             # This should work on any unixy platform ;-)
             # If the user has bothered specifying additional -I and -L flags
             # in OPT and LDFLAGS we might as well use them here.