bpo-29572: Update Windows build to OpenSSL 1.0.2k (GH-442)

diff --git a/PCbuild/readme.txt b/PCbuild/readme.txt
index c04ba4e..8924b3f 100644
--- a/PCbuild/readme.txt
+++ b/PCbuild/readme.txt
@@ -169,7 +169,7 @@
     Homepage:

         http://tukaani.org/xz/

 _ssl

-    Python wrapper for version 1.0.2j of the OpenSSL secure sockets

+    Python wrapper for version 1.0.2k of the OpenSSL secure sockets

     library, which is built by ssl.vcxproj

     Homepage:

         http://www.openssl.org/