rust/qemu-api: Add initial logging support based on C API

rust/qemu-api: Add initial logging support based on C API

A log_mask_ln!() macro is provided which expects similar arguments as the
C version. However, the formatting works as one would expect from Rust.

To maximize code reuse the macro is just a thin wrapper around
qemu_log(). Also, just the bare minimum of logging masks is provided
which should suffice for the current use case of Rust in QEMU.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Link: https://lore.kernel.org/r/20250615112037.11992-2-shentey@gmail.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>