There is no _MIN for unsigned types.

Change-Id: I49c38e51197b750210bdbf28c9cf6db30452a206
diff --git a/libc/include/stdint.h b/libc/include/stdint.h
index f34843c..a6f8505 100644
--- a/libc/include/stdint.h
+++ b/libc/include/stdint.h
@@ -203,7 +203,7 @@
 
 #if defined(__WINT_UNSIGNED__)
 #  define WINT_MAX       UINT32_MAX
-#  define WINT_MIN       UINT32_MIN
+#  define WINT_MIN       0
 #else
 #  define WINT_MAX       INT32_MAX
 #  define WINT_MIN       INT32_MIN