rust: use "objects" for Rust executables as well

rust: use "objects" for Rust executables as well

libqemuutil is not meant be linked as a whole; if modules are enabled, doing
so results in undefined symbols (corresponding to QMP commands) in
rust/qemu-api/rust-qemu-api-integration.

Support for "objects" in Rust executables is available in Meson 1.8.0; use it
to switching to the same dependencies that C targets use: link_with for
libqemuutil, and objects for everything else.

Reported-by: Bernhard Beschow <shentey@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>