INT 62 u - FGDRIVER v4.02 - "FG_VBINIT" - INITIALIZE VIRTUAL BUFFER ENVIRONMENT
	AX = 00D4h
Return: nothing
Notes:	the FGDRIVER functions are rearranged with each major release, but
	  their parameters do not change (see #03474)
	this function must be called before any other virtual buffer functions
	  are used
SeeAlso: AX=00CDh,AX=00D5h