clk: mediatek: cpumux: Propagate struct device where possible

clk: mediatek: cpumux: Propagate struct device where possible

Take a pointer to a struct device in mtk_clk_register_cpumuxes() and
propagate the same to mtk_clk_register_cpumux() => clk_hw_register().
Even though runtime pm is unlikely to be used with CPU muxes, this
helps with code consistency and possibly opens to commonization of
some mtk_clk_register_(x) functions.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: Markus Schneider-Pargmann <msp@baylibre.com>
Tested-by: Miles Chen <miles.chen@mediatek.com>
Link: https://lore.kernel.org/r/20230120092053.182923-5-angelogioacchino.delregno@collabora.com
Tested-by: Mingming Su <mingming.su@mediatek.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>