INT 21 OP - Phar Lap 386/DOS-Extender VMM v2.1c - WRITE PAGE-TABLE ENTRY        
	AX = 251Eh
	BL = address type
	    00h linear address
		ECX = linear address of page table entry to read
	    01h pointer
		ES:ECX -> page table entry to read
	EDX = new value for page table entry
Return: CF clear if successful
	CF set on error
	    EAX = error code
		09h invalid address or NOPAGE option set
		82h not compatible with DPMIsee DOS Protected-Mode Interface
Note:	this call is obsolete; use AX=252Bh/BH=0Ah instead
SeeAlso: AX=251Dh,AX=252Bh/BH=0Ah,INT 31/AX=0507h