windows: Fix Release x64 configuration

Inherit PlatformToolset from the project configuration. This allow the
project to configure PlatformToolset, and aligns the Release x64 build
with other build types.

Fixes #1430
diff --git a/ChangeLog b/ChangeLog
index a4f83d8..8b9bfef 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -44,6 +44,9 @@
      returning. Fixes #2431.
    * Fix typo in net_would_block(). Fixes #528 reported by github-monoculture.
    * Remove redundant include file in timing.c. Fixes #2640 reported by irwir.
+   * Fix Visual Studio Release x64 build configuration by inheriting
+     PlatformToolset from the project configuration. Fixes #1430 reported by
+     irwir.
 
 Changes
    * Return from various debugging routines immediately if the