make mapbuffer Android only module (facebook#44295)

Summary:
Pull Request resolved: facebook#44295

changelog: [internal]

mapbuffer is only used on Android. Let's remove the option to have it compile on iOS.

Reviewed By: NickGerleman

Differential Revision: D56635289

fbshipit-source-id: 1a57c271d21b8aef81179d96b1a6832e7615dd27

Author: sammy-SC

packages/react-native/ReactCommon/react/runtime/platform/ios/ReactCommon/RCTInstance.h

@@ -9,7 +9,6 @@
 
 #import <React/RCTDefines.h>
 #import <jsinspector-modern/ReactCdp.h>
-#import <react/renderer/mapbuffer/MapBuffer.h>
 #import <react/runtime/JSRuntimeFactory.h>
 #import <react/runtime/ReactInstance.h>