Bug 1645766 - Fix build failure in AsyncLogger.h on ppc64le. r=achronop

Thanks to Dan Horák <dan@danny.cz> for the report and fix suggestion.

Differential Revision: https://phabricator.services.mozilla.com/D79683

dom/media/AsyncLogger.h

@@ -9,6 +9,7 @@
 
 #include <atomic>
 #include <thread>
+#include <cinttypes>
 #include "mozilla/ArrayUtils.h"
 #include "mozilla/Attributes.h"
 #include "mozilla/Logging.h"