INT 33 - MS MOUSE - DEFINE GRAPHICS CURSOR
        AX = 0009h
        BX = column of cursor hot spot in bitmap (-16 to 16)
        CX = row of cursor hot spot (-16 to 16)
        ES:DX -> bitmap
                16 words screen mask
                16 words cursor mask
                    each word defines the sixteen pixels of a row, low bit
                    rightmost
SeeAlso: AX=0012h,AX=002Ah,INT 62/AX=007Fh