message: add static to internal functions
diff: #include <malloc.h>
  -RETCODE allocEnv(SQLHENV * out_environment)
  +static RETCODE allocEnv(SQLHENV * out_environment)
  {
  if (nullptr == out_environment)
  return SQL_INVALID_HANDLE;
  @@ -21,7 +21,7 @@ RETCODE allocEnv(SQLHENV * out_environment)
  }
  }
  -RETCODE allocConnect(SQLHENV environment, SQLHDBC * out_connection)
  +static RETCODE allocConnect(SQLHENV environment, SQLHDBC * out_connection)
  {
  if (nullptr == out_connection)
  return SQL_INVALID_HANDLE;
  @@ -37,7 +37,7 @@ RETCODE allocConnect(SQLHENV environment, SQLHDBC * out_connection)
  }
  }
  -RETCODE allocStmt(SQLHDBC connection, SQLHSTMT * out_statement)
  +static RETCODE allocStmt(SQLHDBC connection, SQLHSTMT * out_statement)
  {
  if (nullptr == out_statement || nullptr == connection)
  return SQL_INVALID_HANDLE;
  @@ -54,7 +54,7 @@ RETCODE allocStmt(SQLHDBC connection, SQLHSTMT * out_statement)
  }
  template <typename Handle>
  -RETCODE freeHandle(SQLHANDLE handle_opaque)
  +static RETCODE freeHandle(SQLHANDLE handle_opaque)
  {
  delete reinterpret_cast<Handle *>(handle_opaque);
  handle_opaque = nullptr;
  