INT 10H 4f00H - Query SuperVGA Support

 Expects: AX    4f00H
          ES:DI Addr of buffer to receive an SvgaInfoRec
 Returns: AX    VESA status: AH = 0 means successful (else failed)
                             AL = 4fH means function is supported
          ES:DI buffer contains returned data (if successful)
    Info: This function is used to see if VESA support is present and to
          learn which extended video modes it supports.

          The buffer at ES:DI must be at least 256 bytes long; see
          SvgaInfoRec for a layout of the returned information.  This VESA
          BIOS may place the list of supported modes into your buffer,
          anywhere after offset 12H.

See Also: SVGA
          VESA/SVGA BIOS Services