util/error: expose Error definition to Rust code

This is used to preserve the file and line in a roundtrip from
C Error to Rust and back to C.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

rust/wrapper.h

@@ -60,6 +60,7 @@ typedef enum memory_order {
 #include "hw/qdev-properties-system.h"
 #include "hw/irq.h"
 #include "qapi/error.h"
+#include "qapi/error-internal.h"
 #include "migration/vmstate.h"
 #include "chardev/char-serial.h"
 #include "exec/memattrs.h"