INT 21 - Phar Lap 386/DOS-Ext VMM v3.0 - ALLOCATE DOS MEMORY ABOVE DOS BUFFER

	AX = 2537h
	BX = number of paragraphs to allocate
Return: CF clear if successful
	    AX = real-mode segment of allocated block
	CF set on error
	    AX = error code
		07h MS-DOS memory chain corrupted
		08h insufficient low memory
	    BX = size in paragraphs of largest free block
SeeAlso: AH=48h