Add Korea regions

Author: SibonayK

articles/storage/files/storage-sync-files-planning.md

@@ -240,6 +240,8 @@ Azure File Sync is available only in the following regions:
 | East Asia | Hong Kong SAR |
 | East US | Virginia |
 | East US2 | Virginia |
+| Korea Central| Seoul |
+| Korea South| Busan |
 | Japan East | Tokyo, Saitama |
 | Japan West | Osaka |
 | North Central US | Illinois |