display-caf: fix compile for device which don't use RETIRE_FENCE

the last squashed commit for qcom (http://goo.gl/YU90Ow) broke
compilation for Samsung Galaxy S4 variants.

it set TARGET_DISPLAY_USE_RETIRE_FENCE to true per default.
this sets it to false by default.

thanks to kufikugel for pointing this out in IRC!

Change-Id: Ice5987b8326bed784032731582f66d99e92d5135