suspend: add system_wakeup monitor command

This patch adds the system_wakeup monitor command which will simply
wake up suspended guests.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

qmp-commands.hx

@@ -209,6 +209,27 @@ Example:
 -> { "execute": "cont" }
 <- { "return": {} }
 
+EQMP
+
+    {
+        .name       = "system_wakeup",
+        .args_type  = "",
+        .mhandler.cmd_new = qmp_marshal_input_system_wakeup,
+    },
+
+SQMP
+system_wakeup
+-------------
+
+Wakeup guest from suspend.
+
+Arguments: None.
+
+Example:
+
+-> { "execute": "system_wakeup" }
+<- { "return": {} }
+
 EQMP
 
     {