Int 2F Fn E700  - Multiplex - ??? - Installation Check???                  [-]

   AX = E700h
   BX = 4158h ("AX")
   CX = 4953h ("IS")
   DX = 4845h ("HE")

Return: AL = FFh if installed
       BX = 4C4Fh ("LO") if ??? installed
       CX = 4F4Bh ("OK")
       DX = 4F55h ("OU")
       ES:DI -> ???
Range: AH=C0h to AH=FFh, selected by scanning AH=E7-FFh, then AH=C0h-E6h

Note:  called by QDPMI when its Real to Protected Mode Switch Entry Point
     is called