Restore Interlocked* inline wrappers.

git-svn-id: svn://svn.code.sf.net/p/mingw-w64/code/trunk@6128 4407c894-4637-0410-b4f5-ada5f102cad1
Fix failure due check for _WIN32_WINNT >= 0x501


git-svn-id: svn://svn.code.sf.net/p/mingw-w64/code/trunk@6129 4407c894-4637-0410-b4f5-ada5f102cad1