clk: sunxi: Drop clk.h include

This file is a clock provider, not a clk consumer. Drop the clk.h
include.

Cc: Jens Kuske <jenskuske@gmail.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>