INT 67 - Virtual Control Program InterfaceA simple API for protected-mode programs to allocate memory and switch into or out of protected mode.  See also DOS Protected-Mode Interface. - GET MAX PHYSICAL MEMORY ADDRESS
	AX = DE02h
Return: AH = 00h  successful
	    EDX = physical address of highest 4K memory page
	AH nonzero: failed
SeeAlso: AH=3Fh