Change GPU references to gfx950. (#1695)

CHANGELOG.md

@@ -27,7 +27,7 @@ Full documentation for RCCL is available at [https://rccl.readthedocs.io](https:
 
 ### Added
 
-* Added MSCCL support for multinode MI300/MI350 (i.e., 16 and 32 GPUs). To enable, set the
+* Added MSCCL support for multinode gfx942/gfx950 (i.e., 16 and 32 GPUs). To enable, set the
   environment variable `RCCL_MSCCL_FORCE_ENABLE=1`. Max message size for MSCCL AllGather usage is `12292 * sizeof(datatype) * nGPUs`.
 * Added synchronization before destroying proxy thread to fix a rare hang caused by early termination.