staging: xgifb: replace XGINew_LCD_Wait_Time() with mdelay()

XGINew_LCD_Wait_Time() is implemented using the I/O port 0x61, which is
X86-specific and will fail on other platforms. The code did not make any
sense, but I guess the intention has been to provide a function where
the unit for the delay is milliseconds.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>