iohandler: Introduce iohandler_get_aio_context

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

stubs/iohandler.c

@@ -0,0 +1,8 @@
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "qemu/main-loop.h"
+
+AioContext *iohandler_get_aio_context(void)
+{
+    abort();
+}