Add cstring header explictly as it is removed from HIP

[pramenku]

CP https://github.com/ROCm/rccl-tests/pull/132/files to master

Details
Do not mention proprietary info or link to internal work items in this PR.

Work item: "Internal", or link to GitHub issue (if applicable).

What were the changes?
Add < cstring > header to fix the below errors such as "./common.h:202:10: error: use of undeclared identifier 'strncpy'"

Why were the changes made?
As part of 7.0 breaking changes, HIP runtime header files (hip_runtime.h) stopped including headers such as < cstring > or < string.h > since they were not used in hip runtime. But the apps depending on that header file will fail with the errors and those need to add the header explicitly.

How was the outcome achieved?
By adding < cstring > header.

[pramenku]

This is needed to fix HIP ABI changes and SWDEV-543232 issue is not coming with this branch.

[nileshnegi]

master branch is not used/maintained.

[pramenku]

master branch is not used/maintained.

@nileshnegi I understand. QA was using this branch from Day1 and there was no communucation to switch to develop. We came to know very recently so at least have this branch for now in working state with this PR.

Later, we can remove this branch on permanent basis. Thanks

[nileshnegi]

master branch is not used/maintained.

@nileshnegi I understand. QA was using this branch from Day1 and there was no communucation to switch to develop. We came to know very recently so at least have this branch for now in working state with this PR.

Later, we can remove this branch on permanent basis. Thanks

for now, I have synced the master and develop branches, so this PR is no longer needed.