mstcpip.h, wincrypt.h, ws2tcpip.h : WINAPI_PARTITION_APP fixes

These headers can now be used in Windows Store apps

git-svn-id: svn://svn.code.sf.net/p/mingw-w64/code/trunk@5948 4407c894-4637-0410-b4f5-ada5f102cad1