lguest: write more information to userspace about pending traps.

This is preparation for userspace handling MMIO and ioport accesses.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/drivers/lguest/lg.h b/drivers/lguest/lg.h
index 1c98bf74..020fec5 100644
--- a/drivers/lguest/lg.h
+++ b/drivers/lguest/lg.h
@@ -50,7 +50,8 @@
 	/* Bitmap of what has changed: see CHANGED_* above. */
 	int changed;
 
-	unsigned long pending_notify; /* pfn from LHCALL_NOTIFY */
+	/* Pending operation. */
+	struct lguest_pending pending;
 
 	unsigned long *reg_read; /* register from LHREQ_GETREG */