clk: mediatek: Add mtk_clk_simple_remove()

In commit c58cd0e4 ("clk: mediatek: Add mtk_clk_simple_probe() to
simplify clock providers"), a generic probe function was added to
simplify clk drivers that only needed to support clk gates. However due
to the lack of unregister APIs, a corresponding remove function was not
added.

Now that the unregister APIs have been implemented, add aforementioned
remove function to make it complete.

Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: Miles Chen <miles.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20220208124034.414635-20-wenst@chromium.org


Reviewed-by: Chun-Jie Chen <chun-jie.chen@mediatek.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>