Format of Extended System Configuration Data PCI ECD Extension Function:
Offset	Size	Description	)
 00h	WORD	length of this structure (at least 001Eh, up to 0056h)
 02h	BYTE	01h (selection size)
 03h	BYTE	00h (selection data)
 04h	BYTE	C0h (function information byte) (see #01252)
 05h	BYTE	size of following free-format data (at least 18h, max 50h)
 06h 16 BYTEs	freeform board header (see #01246)
 16h 8N BYTEs	PCI board ID (see #01247) for one to eight boards
Notes:	ECD = Extended Configuration Data; this structure must be the last
	  "function" for a particular PCI board
	AMI BIOS v1.00.05.AX1 sets the length field to 001Ch for entries with
	  a single board ID, apparently treating the field as the length of
	  the remainder of the structure instead of the full structure's length
SeeAlso: #01249