defconfig: enable dbgui driver on 8909

Enable debugUI driver on 8909 that allows capturing data on certain
triggers as well as send the captured data as trace output. This will
help with debugging issues.

Change-Id: I46091e46d1814a83d4ec36ec5ab9b311b81847a8
Signed-off-by: Xiaogang Cui <xiaogang@codeaurora.org>