staging/xgifb: Remove uneccessary/simply if in XGINew_GetXG20DRAMType

Instead of storing the value in a temp variable, anding it with 1 and
assign data conditionally we can assign the value directly.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>