dbexit() in mssql_odbx_finish() was missing backend is thread safe
dbexit() in mssql_odbx_finish() was missing
backend is thread safe

nsendetzky/libopendbx,nos3/libopendbx,nos3/libopendbx,nos3/libopendbx,nsendetzky/libopendbx,nsendetzky/libopendbx