memory-device: move stubs out of stubs/

Since the memory-device stubs are needed exactly when the Kconfig symbols are not
needed, move them to hw/mem/.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20240408155330.522792-15-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
3 files changed