rockchip: rk3288: Use rk3288-cru.h from dts/upstream

rockchip: rk3288: Use rk3288-cru.h from dts/upstream

clock/rk3288-cru.h in include/dt-bindings is almost identical to the
version in dts/upstream, remove the copy from include/dt-bindings to
only use the version from dts/upstream.

One clk, SCLK_MAC_PLL, is not part of the upstream bindings, this clk is
not used by upstream, in-tree or vendor DTs and can safely be dropped.

No functional change to board DTs is intended with this removal.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>