Make language std configurable. (#75519)
RocksDB 7 starts to use C++17 in header.
We should make this configurable, in case user needs higher std version.
List of files to changed is found by `git grep 'CMAKE_[^_]*_STANDARD'`.
Doc string is from CMake code.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/75519
Approved by: https://github.com/malfet
