INT 21 - FlashTek X-32VM - VIRTUAL MEMORY MANAGEMENT - PAGE LOCKING
        AX = 252Bh
        BH = function
            05h lock pages
            06h unlock pages
        BL = address type
            00h linear address
                ECX = linear start address of memory region
            01h segmented address
                ES:ECX -> start of memory region
        EDX = size of memory region in bytes
Return: CF clear if successful
        CF set on error
Note:   if X-32 is not using virtual memory, this function always succeeds