windows: add cmsghdr and pktinfo structures

[database64128]

• CMSGHDR from ws2def.h, corresponds to Cmsghdr in unix
• IN_PKTINFO from ws2ipdef.h, corresponds to InetPktinfo in unix
• IN6_PKTINFO from ws2ipdef.h, corresponds to Inet6Pktinfo in unix

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Patch Set 1:

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Patch Set 1: Commit-Queue+1

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Patch Set 1:

Dry run: CV is trying the patch.

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Patch Set 1: -Commit-Queue

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This CL has passed the run

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Patch Set 1: LUCI-TryBot-Result+1

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Patch Set 1:

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Patch Set 1:

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Patch Set 1:

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This PR (HEAD: 7377c79) has been imported to Gerrit for code review.

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Message from Ian Chen:

Patch Set 1:

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