Prefer botan-3 and prevent linking to botan-2, as security/botan2 is currently
marked for removal. [1] Although we depend on libbotan-3.so for the BOTAN
option, previous code would link to libbotan-2.so if installed.

[1] https://cgit.freebsd.org/ports/commit/?id=eb1217e8e983cae63d99af35ac6de924b56691ab

--- plugins/qca-botan/CMakeLists.txt.orig	2025-03-09 12:09:03 UTC
+++ plugins/qca-botan/CMakeLists.txt
@@ -1,13 +1,10 @@ find_package(PkgConfig REQUIRED)
 find_package(PkgConfig REQUIRED)
 
-pkg_check_modules(BOTAN IMPORTED_TARGET botan-2)
-if(NOT BOTAN_FOUND)
-  pkg_check_modules(BOTAN IMPORTED_TARGET botan-3)
-  if(BOTAN_FOUND)
-    set(CMAKE_CXX_STANDARD 20)
-    set(CMAKE_CXX_STANDARD_REQUIRED ON)
-    set(CMAKE_CXX_EXTENSIONS OFF)
-  endif()
+pkg_check_modules(BOTAN IMPORTED_TARGET botan-3)
+if(BOTAN_FOUND)
+  set(CMAKE_CXX_STANDARD 20)
+  set(CMAKE_CXX_STANDARD_REQUIRED ON)
+  set(CMAKE_CXX_EXTENSIONS OFF)
 endif()
 
 if(WITH_botan_PLUGIN STREQUAL "yes" AND NOT BOTAN_FOUND)