remove preconfig state

The preconfig state is only used if -incoming is not specified, which
makes the RunState state machine more tricky than it need be.  However
there is already an equivalent condition which works even with -incoming,
namely qdev_hotplug.  Use it instead of a separate runstate.

Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/stubs/qmp-command-available.c b/stubs/qmp-command-available.c
new file mode 100644
index 0000000..46540af
--- /dev/null
+++ b/stubs/qmp-command-available.c
@@ -0,0 +1,7 @@
+#include "qemu/osdep.h"
+#include "qapi/qmp/dispatch.h"
+
+bool qmp_command_available(const QmpCommand *cmd, Error **errp)
+{
+    return true;
+}