[Objective-C] Remove CocoaPods ignores

We shouldn't be ignoring these, it's down to the user and we shouldn't enforce them to ignore the `Pods/` directory

http://guides.cocoapods.org/using/using-cocoapods.html#should-i-ignore-the-pods-directory-in-source-control?

Objective-C.gitignore

@@ -15,6 +15,3 @@ profile
 DerivedData
 *.hmap
 *.ipa
-
-# CocoaPods
-Pods