remove libpng version probing on windows

jbmohler · jbmohler · commit cc402cf816b8 · 2014-09-12T08:32:36.000-04:00
diff --git a/setupext.py b/setupext.py
@@ -1003,6 +1003,9 @@ class Png(SetupPackage):
     name = "png"
 
     def check(self):
+        if sys.platform == 'win32':
+            return "Unknown version"
+
         status, output = getstatusoutput("libpng-config --version")
         if status == 0:
             version = output
