SWDEV-497636 - Updated CHANGELOG

Updated CHANGELOG to include the performance fix for
kernel launch latency with increasing number of idle streams.

Change-Id: I509e14cb8f8cd3abe61c6ede78808e96ef8f06e1

CHANGELOG.md

@@ -8,6 +8,10 @@ Full documentation for HIP is available at [rocm.docs.amd.com](https://rocm.docs
 * Added new environment variable
     - `DEBUG_HIP_7_PREVIEW` This is used for enabling the backward incompatible changes before the next major ROCm release 7.0. By default this is set to 0. Users can set this variable to 0x1, to match the behavior of hipGetLastError with its corresponding CUDA API.
 
+### Resolved issues
+* Fixed a performance issue where the kernel launch efficiency on the default stream declined
+  with increasing number of user-created streams.
+
 ## HIP 6.3 for ROCm 6.3
 
 ### Changed