clk: rockchip: Fix memory leak in rockchip_clk_register_pll()

In the Linux kernel, the following vulnerability has been resolved: clk: rockchip: Fix memory leak in rockchip_clk_register_pll() If clk_register() fails, @pll->rate_table may have allocated memory by kmemdup(), so it needs to be freed, otherwise will cause memory leak issue, this patch fixes it.