[mutter] idle-monitor: Remove redundant type cast

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 26b08d87a8ff31ac9e9ebecde75de5ac94a73efb
Author: Jonas Ådahl <jadahl gmail com>
Date:   Mon Sep 16 16:36:05 2019 +0200

    idle-monitor: Remove redundant type cast
    
    No need to type cast a `MetaIdleMonitorWatch *` to a
    `MetaIdleMonitorWatch *`.
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/799

 src/backends/meta-idle-monitor.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/backends/meta-idle-monitor.c b/src/backends/meta-idle-monitor.c
index de1c7e0ba..e5124abc1 100644
--- a/src/backends/meta-idle-monitor.c
+++ b/src/backends/meta-idle-monitor.c
@@ -511,7 +511,7 @@ meta_idle_monitor_reset_idletime (MetaIdleMonitor *monitor)
 
       if (watch->timeout_msec == 0)
         {
-          meta_idle_monitor_watch_fire ((MetaIdleMonitorWatch *) watch);
+          meta_idle_monitor_watch_fire (watch);
         }
       else
         {