INT 62 u - FGDRIVER v4.02 - "FG_MEMORY" - GET SIZE OF VIDEO MEMORY
	AX = 0072h
Return: AX = size of video memory in KB
Notes:	the FGDRIVER functions are rearranged with each major release, but
	  their parameters do not change (see #03474 at AX=0000h)
	You must first call "FG_SVGAINIT" (see AX=00C1h) before using this
	  function
SeeAlso: AX=0071h