Update platform support list (#7827)

Perf and FIAM now have tvOS support

Author: paulb777

README.md

@@ -272,13 +272,14 @@ To install, add a subset of the following to the Podfile:
 
 ```
 pod 'Firebase/ABTesting'
-pod 'Firebase/Auth'          # Limited watchOS support
+pod 'Firebase/Auth'           # Limited watchOS support
 pod 'Firebase/Crashlytics'
-pod 'Firebase/Database'      # No watchOS support yet
-pod 'Firebase/Firestore'     # No watchOS support yet
-pod 'Firebase/Functions'     # No watchOS support yet
+pod 'Firebase/Database'       # No watchOS support yet
+pod 'Firebase/Firestore'      # No watchOS support yet
+pod 'Firebase/Functions'      # No watchOS support yet
+pod 'Firebase/InAppMessaging' # No macOS, watchOS, and Catalyst support yet
 pod 'Firebase/Messaging'
-pod 'Firebase/Performance'   # No macOS, tvOS, watchOS, and Catalyst support yet
+pod 'Firebase/Performance'    # No macOS, watchOS, and Catalyst support yet
 pod 'Firebase/RemoteConfig'
 pod 'Firebase/Storage'
 ```