Fix various typos

Mainly fix typos in comments, but also some minor code changes:

* Rename `apply_on_poiner` to `apply_on_pointer`.
* Rename `ImeState::Commited` to `ImeState::Committed`
* Correct `cfg_attr` usage: `wayland_platfrom` -> `wayland_platform`.

src/platform_impl/ios/event_loop.rs

@@ -76,7 +76,7 @@ impl EventLoopWindowTarget {
 
     pub(crate) fn exit(&self) {
         // https://developer.apple.com/library/archive/qa/qa1561/_index.html
-        // it is not possible to quit an iOS app gracefully and programatically
+        // it is not possible to quit an iOS app gracefully and programmatically
         log::warn!("`ControlFlow::Exit` ignored on iOS");
     }