INT 21 - European MSDOS 4.0 - "RESUME" - RESTART A PROCESS
        AH = 82h
        BX = flag (00h resume command subtree, 01h only specified process)
        CX = Process ID of head of command subtree
Return: CF clear if successful
        CF set on error
            AX = error code (no such process)
Desc:   restart a previously-suspended process or a process and all of its
          children
SeeAlso: INT 15/AX=101Eh