defconfig: set cnss driver as asynchronous

cnss driver takes long time to run so it's better we
set it as asynchronous. And we need to enable
CONFIG_PLATFORM_AUTO first which removes the big
lock for platform driver probe. Without this, setting
drivers as synchronous will not help.

Change-Id: I6a4fb29305f65239b2de8cd9b8a47379481b9b38
Signed-off-by: Jiacheng Zheng <jiaczhen@codeaurora.org>