clk: mediatek: fix unregister function in mtk_clk_register_dividers cleanup

clk: mediatek: fix unregister function in mtk_clk_register_dividers cleanup

When the cleanup paths for the various clk register APIs in the MediaTek
clk library were added, the one in the dividers type used the wrong type
of unregister function. This would result in incorrect dereferencing of
the clk pointer and freeing of invalid pointers.

Fix this by switching to the correct type of clk unregistration call.

Fixes: 088b81b41663 ("clk: mediatek: mtk: Implement error handling in register APIs")
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20220926102523.2367530-2-wenst@chromium.org
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>