INT 10 - Chips & Technologies '64300' BIOS - GET REFRESH RATE

	AX = 5F04h
	BL = video mode number
Return: AL = 5Fh if function supported
	    AH = status
		00h unsuccessful
		01h successful
		    BH = available refresh rates (see #00182)
		    BL = currently-set refresh rate (see #00182)
SeeAlso: AX=5F03h"64300",AX=5F05h"64300"