INT 62 u - FGDRIVER v4.02 - "FG_TCMASK" - SET TRANSPARENT COLORS
	AX = 00C5h
	BX = colors to consider transparent (bit 0 = color 0, etc)
Notes:	the FGDRIVER functions are rearranged with each major release, but
	  their parameters do not change (see #03474 at AX=0000h)
	This call is ignored in text modes
	The specified colors are considered transparent by "FG_TCXFER"
SeeAlso: AX=00C4h,AX=00C6h