Update CHANGELOG for #15641

Author: gdavison

CHANGELOG.md

@@ -8,6 +8,8 @@ ENHANCEMENTS
 
 * resource/aws_network_interface: Add `ipv6_addresses` and `ipv6_address_count` arguments [GH-12281]
 * resource/aws_cloudwatch_event_target: Add validation to `input_transformer.input_paths` map [GH-15669]
+* resource/fsx_lustre_file_system: Increased maximum `automatic_backup_retention_days` from 35 to 90 [GH-15641]
+* resource/fsx_windows_file_system: Increased maximum `automatic_backup_retention_days` from 35 to 90 [GH-15641]
 
 ## 3.11.0 (October 15, 2020)