feat: Update Kotlin 2.0.21-RC eap release details (#4465)

* Update Kotlin 2.0.21-RC eap release details

* Update KMP compatibility guide to add support for Xcode 16

This change is already approved by Timofey Solonin

* update: fixed eap versioning

* chore: removed support for Xcode until 2.0.21 is stable

* chore: update date

docs/topics/eap.md

@@ -57,4 +57,14 @@ check [our instructions on how to configure your build to support this version](
             <p>For more details, please refer to the <a href="https://github.com/JetBrains/kotlin/releases/tag/v2.1.0-Beta1">changelog</a> or <a href="whatsnew-eap.md">What's new in Kotlin 2.1.0-Beta1</a>.</p>
         </td>
     </tr>
+    <tr>
+        <td><strong>2.0.21-RC</strong>
+            <p>Released: <strong>October 1, 2024</strong></p>
+            <p><a href="https://github.com/JetBrains/kotlin/releases/tag/v2.0.21-RC" target="_blank">Release on GitHub</a></p>
+        </td>
+        <td>
+            <p>A bug fix release for Kotlin 2.0.20</p>
+            <p>For more details, please refer to the <a href="https://github.com/JetBrains/kotlin/releases/tag/v2.0.21-RC">changelog</a>.</p>
+        </td>
+    </tr>
 </table>