Revert "Switching the iPhone architecture setting to Universal."

This reverts commit 81b64934d146113b823800bdfa127521ebda1867.

ProjectSettings/ProjectSettings.asset

     26: UNITY_POST_PROCESSING_STACK_V2
     27: UNITY_POST_PROCESSING_STACK_V2
   platformArchitecture:
-    iPhone: 2
+    iPhone: 1
   scriptingBackend: {}
   il2cppCompilerConfiguration: {}
   managedStrippingLevel: {}