[Pulldown] Restore missing libc files

[aelovikov-intel]

Not sure what went wrong during pulldowns, but somehow we're missing files in a sub-directory where no customizations are expected. Restored via

$ git checkout $(git merge-base origin/sycl origin/main) -- libc

[bader]

There should be no difference between the libc in main and sycl branches.
@jsji, could you please investigate why we lost these files and propose pulldown process improvements to avoid similar issues in the future?

[github-actions]

@intel/llvm-gatekeepers please consider merging

[jsji]

There should be no difference between the libc in main and sycl branches. @jsji, could you please investigate why we lost these files and propose pulldown process improvements to avoid similar issues in the future?

This was deleted in conflict resolution 8f5f701 , which is an obvious conflict resolution error when sycl branch is being merged to sycl-web.

*   8f5f70120d3f - (2025-03-03) Merge from 'sycl' to 'sycl-web' (1 commits) - Chenyang Liu
|\
| *   799c7be39443 - (2025-03-03) LLVM and SPIRV-LLVM-Translator pulldown (WW09 2025) - bb-sycl

In this case, the new file is added in llorg, merged in sycl-web, but not yet in sycl branch, so when the sycl branch is merged to sycl-web, there will be a modify/delete conflict. We should keep the file in tree, instead of deleting it.
Current tooling is doing right, it was force deleted, so this should be a pulldown coordinator experience issue that we probably have to tolerate.

Author: Chenyang Liu <chenyang.liu@intel.com>
Date:   Mon Mar 3 10:29:31 2025 -0800

    Merge from 'sycl' to 'sycl-web' (1 commits)

      CONFLICT (rename/delete): libclc/generic/include/core/shared/clc_min.h renamed to libc/include/endian.h.def in HEAD, but deleted in 799c7be394437426197bc73d8c0e5d8746e1c4e7.
      CONFLICT (modify/delete): libc/include/endian.h.def deleted in 799c7be394437426197bc73d8c0e5d8746e1c4e7 and modified in HEAD.  Version HEAD of libc/include/endian.h.def left in tree.