qemu_monitor: Fix tray-open attribute in query-block

With our code, we fail to query for tray-open attribute currently.
That's because in HMP it is 'tray-open' and in QMP it's 'tray_open'.
It always has been. However, we got it exactly the opposite.

src/qemu/qemu_monitor_json.c

@@ -1585,10 +1585,10 @@ int qemuMonitorJSONGetBlockInfo(qemuMonitorPtr mon,
             goto cleanup;
         }
 
-        /* Don't check for success here, because 'tray-open' is presented iff
+        /* Don't check for success here, because 'tray_open' is presented iff
          * medium is ejected.
          */
-        ignore_value(virJSONValueObjectGetBoolean(dev, "tray-open",
+        ignore_value(virJSONValueObjectGetBoolean(dev, "tray_open",
                                                   &info->tray_open));
 
         /* Missing io-status indicates no error */

src/qemu/qemu_monitor_text.c

@@ -809,10 +809,10 @@ int qemuMonitorTextGetBlockInfo(qemuMonitorPtr mon,
                         VIR_DEBUG("error reading locked: %s", p);
                     else
                         info->locked = (tmp != 0);
-                } else if (STRPREFIX(p, "tray_open=")) {
-                    p += strlen("tray_open=");
+                } else if (STRPREFIX(p, "tray-open=")) {
+                    p += strlen("tray-open=");
                     if (virStrToLong_i(p, &dummy, 10, &tmp) == -1)
-                        VIR_DEBUG("error reading tray_open: %s", p);
+                        VIR_DEBUG("error reading tray-open: %s", p);
                     else
                         info->tray_open = (tmp != 0);
                 } else if (STRPREFIX(p, "io-status=")) {