arch: arm64: Enable APPENDED_DTB in Makefile and defconfig

Update the makefile to enable generation of appeneded dtbs and enable
the kernel config for Appended DTB.

Change-Id: Ia5dcf928eb9e8336f4483b3e0b9f303d6b946961
Signed-off-by: Channagoud Kadabi <ckadabi@codeaurora.org>
4 files changed