5a1ee6077b
machine_init_done is not the right flag to check when preconfig is taken into account; for example "./qemu-system-x86_64 -serial mon:stdio -preconfig" does not print the QEMU monitor header until after exit_preconfig. Add back a custom bool for mux character devices. This partially undoes commit c7278b4355 ("chardev: introduce chr_machine_done hook", 2018-03-12), but it keeps the cleaner logic using a function pointer in ChardevClass. Reviewed-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>