py: Disable -Winvalid-offsetof

A "small vector" implementation has been introduced in the latest version of
pybind11 (3.0.2), which might use `offsetof()` on a non standard layout type.
This triggers the `invalid-offsetof` warning.

So disable it for the python bindings.

Link: https://github.com/pybind/pybind11/pull/5824
Signed-off-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/py/libcamera/meson.build

@@ -53,6 +53,7 @@ pycamera_deps = [
 
 pycamera_args = [
     '-fvisibility=hidden',
+    '-Wno-invalid-offsetof',
     '-Wno-shadow',
     '-DPYBIND11_USE_SMART_HOLDER_AS_DEFAULT',
 ]