[sanitizer] Implement GetRSS on Windows

Summary:
Pretty straightforward, returning the `WorkingSetSize` of a
`PROCESS_MEMORY_COUNTERS` structure. AFAIU, `GetProcessMemoryInfo` is in
`kernel32.lib` for Windows 7 and above. Support for earlier Windows versions
would require `psapi.lib`, but I don't think those are supported by ASan?

Reviewers: alekseyshl, rnk, vitalybuka

Reviewed By: vitalybuka

Subscribers: vitalybuka, kubamracek, delcypher, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D42822

llvm-svn: 325020