Add missing 16.6.1 changelog entry

Author: gaearon

CHANGELOG.md

@@ -47,6 +47,7 @@ This release was published in a broken state and should be skipped.
 
 * Fallback should not remount every time a promise resolves. ([@acdlite](https://github.com/acdlite) in [#14083](https://github.com/facebook/react/pull/14083))
 * Fix bug where Suspense keeps showing fallback even after everything finishes loading. ([@acdlite](https://github.com/acdlite) in [#14083](https://github.com/facebook/react/pull/14083))
+* Fix a crash when Suspense finishes loading in IE11. ([@sophiebits](https://github.com/sophiebits) in [#14126](https://github.com/facebook/react/pull/14126))
 * Fix unresolved default props in lifecycle methods of a lazy component. ([@gaearon](https://github.com/gaearon) in [#14112](https://github.com/facebook/react/pull/14112))
 * Fix bug when recovering from an error thrown during complete phase. ([@gaearon](https://github.com/gaearon) in [#14104](https://github.com/facebook/react/pull/14104))