Remove Xcode 12.5 post install workaround (#39482)

Summary:
Now that we updated folly in 17154a6, we should pick up facebook/folly@4a8837f and probably don't need this post install phase anymore

## Changelog:

[IOS] [REMOVED] - Remove Xcode 12.5 post install workaround

Pull Request resolved: #39482

Test Plan: CI should pass

Reviewed By: cipolleschi

Differential Revision: D49328614

Pulled By: NickGerleman

fbshipit-source-id: 05fa0b6d41d07ac552e2b536fbf3a732a31ba713

Author: Saadnajmi

packages/react-native/scripts/react_native_pods.rb

@@ -379,23 +379,3 @@ def use_react_native_codegen!(spec, options={})
     :show_env_vars_in_log => true
   }
 end
-
-# This provides a post_install workaround for build issues related Xcode 12.5 and Apple Silicon machines.
-# Call this in the app's main Podfile's post_install hook.
-# See https://github.com/facebook/react-native/issues/31480#issuecomment-902912841 for more context.
-# Actual fix was authored by https://github.com/mikehardy.
-# New app template will call this for now until the underlying issue is resolved.
-def __apply_Xcode_12_5_M1_post_install_workaround(installer)
-  # NOTE: This fix is still required due to RCT-Folly
-  # creating a function with a better name but keeping the
-  # previous for backward compatibility
-  __fix_double_definition_of_clockid_in_folly()
-end
-
-def __fix_double_definition_of_clockid_in_folly()
-  # "Time.h:52:17: error: typedef redefinition with different types"
-  # We need to make a patch to RCT-Folly - remove the `__IPHONE_OS_VERSION_MIN_REQUIRED` check.
-  # See https://github.com/facebook/flipper/issues/834 for more details.
-  time_header = "#{Pod::Config.instance.installation_root.to_s}/Pods/RCT-Folly/folly/portability/Time.h"
-  `sed -i -e  $'s/ && (__IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_10_0)//' '#{time_header}'`
-end

packages/react-native/template/ios/Podfile

@@ -51,6 +51,5 @@ target 'HelloWorld' do
       config[:reactNativePath],
       :mac_catalyst_enabled => false
     )
-    __fix_double_definition_of_clockid_in_folly()
   end
 end

packages/rn-tester/Podfile

@@ -87,5 +87,4 @@ end
 
 post_install do |installer|
   react_native_post_install(installer, @prefix_path, :mac_catalyst_enabled => false)
-  __fix_double_definition_of_clockid_in_folly()
 end