INT 2F - FaxBIOS interface - INSTALLATION CHECK                                 
	AX = 8000h
	DX = 0000h
	DI = 0000h
Return: AL = FFh if installed
	DX:DI -> signature "FaxBiosjpc"
Range:	AH=80h to AH=FFh, selected by scanning multiplex numbers for signature
SeeAlso: AH=2Ah,AX=80FBh