INT 10 - EGA Register Interface Library - READ REGISTER SET
        AH = F4h
        CX = number of registers to read (>1)
        ES:BX -> table of records (see below)
Return: register values in table filled in
Note:   the RIL is provided by EGA.SYS, the Microsoft Mouse driver, the OS/2
          compatibility box, and others
SeeAlso: AH=F2h,AH=F5h

Format of entries in table of register records:
Offset  Size    Description
 00h    WORD    group index
                Pointer/data chips
                   00h CRTC (3B4h mono modes, 3D4h color modes)
                   08h Sequencer 3C4h
                   10h Graphics Controller 3CEh
                   18h Attribute Controller 3C0h
                Single registers
                   20h Miscellaneous Output register 3C2h
                   28h Feature Control register (3BAh mono modes, 3DAh color)
                   30h Graphics 1 Position register 3CCh
                   38h Graphics 2 Position register 3CAh
 02h    BYTE    register number (0 for single registers)
 03h    BYTE    register value