arm64: defconfig: Disable wakeup sources garbage collector for userspace

Userspace garbage collector for the wakeup sources is needed only
for the debugging and default debug android builds. It should not be
required for the performance configuration builds.

Change-Id: I48b0a50ba6c946d80ce34b16892dec2f4134ce72
Signed-off-by: Trilok Soni <tsoni@codeaurora.org>