INT 4B - Virtual DMA Specification - RELEASE DMA BUFFFER

	AX = 8108h
	DX = flags
	    bit 0: reserved (zero)
	    bit 1: data should be copied out of buffer
	    bits 2-15 reserved (zero)
	ES:DI -> DMA descriptor structure (see #03221,#03222) with buffer ID set
		  (also region size/region offset/segment if DX bit 1 set)
Return: CF clear if successful
	CF set on error
	    AL = error code (see #03218)
BUG:	under Windows 3.0 Enhanced mode, you must specify that data be copied
	  for this function to work correctly
SeeAlso: AX=8107h