Commit 6c97e3b0f4 for freeswitch.com

commit 6c97e3b0f4d8858c51dc834ad6957387067621fb
Author: Andrey Volk <andywolk@gmail.com>
Date:   Wed Dec 29 19:07:54 2021 +0300

    [Core] Fix missing mutex unlock in switch_ivr_dmachine_ping()

diff --git a/src/switch_ivr_async.c b/src/switch_ivr_async.c
index 6dfdcf7248..d00b75d40c 100644
--- a/src/switch_ivr_async.c
+++ b/src/switch_ivr_async.c
@@ -546,6 +546,7 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_dmachine_ping(switch_ivr_dmachine_t *
 	}

 	if (dmachine->pinging) {
+		switch_mutex_unlock(dmachine->mutex);
 		return SWITCH_STATUS_BREAK;
 	}