Format of MS-DOS/PC-DOS/OS2/WinNT/PTS-DOS COUNTRY.SYS country-subfunc header:
Offset	Size	Description	)
 00h	WORD	number of subfunction entries following
 02h		N subfunction entries
		Offset	Size	Description
		 00h	WORD	length of subfunction entry, not counting this
				  word (usually 06h)
		 02h	WORD	subfunction ID
				(value passed to INT 21/AH=65h in AL)
		 04h	DWORD	offset within file of subfunction data entry
				  (see #02622)
SeeAlso: #02620