mssql: support windows (#10336)

thirdparty/mssql/include/.gitignore

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+*
+
+!.gitignore
+!mssql.h

thirdparty/mssql/include/mssql.h

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+// Hacking some headers in windows.
+// sql headers using UNICODE to change function signatures.
+// Currently Linux bindings do not use unicode SQL C bindings,
+// So we turn off the UNICODE to make it compile on windows.
+// For future Unicode support, please raise a issue.
+
+#include <windows.h>
+#include <sal.h>
+
+#ifdef UNICODE
+// Turn off unicode macro and turn back on, so it only affects sql headers
+#undef UNICODE
+#include <sql.h>
+#include <sqlext.h>
+#define UNICODE
+
+#else
+#include <sql.h>
+#include <sqlext.h>
+#endif