staging: vc04_services: use DEFINE_MUTEX() for mutex lock

mutex lock can be initialized automatically with DEFINE_MUTEX()
rather than explicitly calling mutex_init().
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Link: https://lore.kernel.org/r/20201224132528.31558-1-zhengyongjun3@huawei.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/vc04_services/interface/vchiq_arm/vchiq_connected.c

@@ -12,13 +12,12 @@ static   int                        g_connected;
 static   int                        g_num_deferred_callbacks;
 static   VCHIQ_CONNECTED_CALLBACK_T g_deferred_callback[MAX_CALLBACKS];
 static   int                        g_once_init;
-static   struct mutex               g_connected_mutex;
+static   DEFINE_MUTEX(g_connected_mutex);
 
 /* Function to initialize our lock */
 static void connected_init(void)
 {
 	if (!g_once_init) {
-		mutex_init(&g_connected_mutex);
 		g_once_init = 1;
 	}
 }