Summary:
Improve memkind library detection in build_detect_platform:
- The current position of -lmemkind does not work with all versions of gcc
- LDFLAGS allows specifying non-standard library path through EXTRA_LDFLAGS
After the change, the options match TBB detection.
This is a follow-up to https://github.com/facebook/rocksdb/issues/6214.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9134
Reviewed By: ajkr, mrambacher
Differential Revision: D32192028
fbshipit-source-id: 115fafe8d93f1fe6aaf80afb32b2cb67aad074c7