[libxml2] Update CMake project version

[Nick Wellnhofer <nwellnhof src gnome org>]

commit a46e85f6698af712dc8bee683431c70d35e456ff
Author: Markus Rickert <rickert fortiss org>
Date:   Sat May 22 15:20:46 2021 +0200

    Update CMake project version

 CMakeLists.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/CMakeLists.txt b/CMakeLists.txt
index e8bf2429..b4c0c794 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.15)
 
-project(libxml2 VERSION 2.9.10 LANGUAGES C)
+project(libxml2 VERSION 2.9.12 LANGUAGES C)
 
 include(CheckCSourceCompiles)
 include(CheckFunctionExists)