arm64: berlin: Select DW_APB_TIMER_OF

Berlin SoCs always contain some DW APB timers which can be used as an
always-on broadcast timer.

Link: https://lore.kernel.org/r/20201009150536.214181fb@xhacker.debian


Cc: <stable@vger.kernel.org> # v3.14+
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>