defconfig: Enable USB gadget uevents on QCS405

On QCS405 enable USB gadget events for the android_usb
class creation and the userspace can receive the
USB gadget uevents.

Change-Id: I6db4acd892710500a140465dd24839a0b1ade2f2
Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>