linux::sock_ctrl_msg::tests::buffer_len assert failure on armhf

[mjt0k]

failures:

---- linux::sock_ctrl_msg::tests::buffer_len stdout ----
thread 'linux::sock_ctrl_msg::tests::buffer_len' panicked at 'assertion failed: `(left == right)`
  left: `20`,
 right: `16`', src/linux/sock_ctrl_msg.rs:479:13

This is this code:
        assert_eq!(
            CMSG_SPACE!(size_of::()),
            size_of::() + size_of::()
        );

I guess this is due to wrong size/type used in some structure.

https://ci.debian.net/data/autopkgtest/testing/armhf/r/rust-vmm-sys-util/32900885/log.gz

[plugwash]

The structures themselves look fine to me, it's the test code that seems to be wrong.

Patch at (along with issue 191) https://salsa.debian.org/rust-team/debcargo-conf/-/blob/1d296fda82959651ff7358066dcb4425941a2060/src/vmm-sys-util/debian/patches/fix-tests-32-bit.patch