Make --vsenv a readonly builtin option

We need to remember its value when reconfiguring, but the Build object
is not reused, only coredata is.

This also makes CLI more consistent by allowing `-Dvsenv=true` syntax.

Fixes: #11309

1 files changed, 1 insertions, 0 deletions

diff --git a/mesonbuild/utils/universal.py b/mesonbuild/utils/universal.py
index c96930c..e06eaaa 100644
--- a/mesonbuild/utils/universal.py
+++ b/mesonbuild/utils/universal.py
@@ -2144,6 +2144,7 @@ _BUILTIN_NAMES = {
     'force_fallback_for',
     'pkg_config_path',
     'cmake_prefix_path',
+    'vsenv',
 }