[libxml2] cmake: Set SOVERSION

[Nick Wellnhofer <nwellnhof src gnome org>]

commit 796c830a2f113b73a81195b6fad8c66e66b4a751
Author: Nick Wellnhofer <wellnhofer aevum de>
Date:   Tue Sep 20 14:30:19 2022 +0200

    cmake: Set SOVERSION
    
    Fixes #410.

 CMakeLists.txt | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/CMakeLists.txt b/CMakeLists.txt
index b16af1f0..c3dba6c6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -415,6 +415,7 @@ set_target_properties(
        POSITION_INDEPENDENT_CODE ON
        PREFIX lib
        VERSION ${PROJECT_VERSION}
+        SOVERSION ${LIBXML_MAJOR_VERSION}
 )
 
 if(MSVC)