VOID
SepAppendPrimaryGroup(
      __in PTOKEN Token,
      __in PSID PSid
  );


Routine Description:

    Add a primary group SID to the available space at the end of the dynamic
    part of the token.  It is the caller's responsibility to ensure that the
    primary group SID fits within the available space of the dynamic part of
    the token.

    The token is assumed to be locked for write access before calling
    this routine.

Arguments:

    Token - Pointer to the token.

    PSid - Pointer to the SID to add.

Return Value:

    None.