clk: rockchip: fix rk3288 cpuclk core dividers

Commit 0e5bdb3f (clk: rockchip: switch to using the new cpuclk type
for armclk) didn't take into account that the divider used on rk3288
are of the (n+1) type.

The rk3066 and rk3188 socs use more complex divider types making it
necessary for the list-elements to be the real register-values to write.

Therefore reduce divider values in the table accordingly so that they
really are the values that should be written to the registers and match
the dividers actually specified for the rk3288.

Reported-by: Sonny Rao <sonnyrao@chromium.org>
Fixes: 0e5bdb3f ("clk: rockchip: switch to using the new cpuclk type for armclk")
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Cc: stable@vger.kernel.org