RDBSSLIB and RXCE: errors compiling with _WIN32_WINNT=0x600

This issue is a part of CORE-12596.

For the time being, I am locally disabling rdbsslib, rxce and dependent nfs.

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When I try to compile as "NT6", assuming my WIP patch is correct enough, I get:

• rdbsslib: 82 errors.
• rxce: 36 errors.

These two are the only components with so many reported errors.