Document ROCm 7.1+ requirement for hipMemImportFromShareableHandle

hipMemImportFromShareableHandle segfaults on ROCm 7.0 due to inverted
MemObjMap logic in ROCm/clr hip_vm.cpp (removes instead of adds imported
memory objects, causing null dereference in hipMemSetAccess).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: mawad-amd

iris/allocators/vmem_chunked_allocator.py

@@ -22,7 +22,6 @@
 Requires ROCm 7.1+. hipMemImportFromShareableHandle segfaults on ROCm 7.0
 due to inverted MemObjMap logic in ROCm/clr hip_vm.cpp (removes instead of
 adds imported memory objects, leading to null dereference in hipMemSetAccess).
-Fixed in ROCm 7.1: https://github.com/ROCm/clr/blob/rocm-7.1.0/hipamd/src/hip_vm.cpp
 """
 
 import math