Update submodule rileylink_ios: Hack to still support Xcode 12

bjornoleh · bjornoleh · commit c63607cc994a · 2021-09-21T17:09:01.000+02:00
diff --git a/rileylink_ios b/rileylink_ios
@@ -1 +1 @@
-Subproject commit 8125112c66f53b0f3e3693fd2486426111a37ca0
+Subproject commit 15d19970f589d1678a486a9b7cfa2430111ee3ea
