clk: mediatek: reset: Change return type for clock reset register function

To deal with error handling, we change the function return type from
void to int for mtk_clk_register_rst_ctrl().

Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Link: https://lore.kernel.org/r/20220523093346.28493-10-rex-bc.chen@mediatek.com


Signed-off-by: Stephen Boyd <sboyd@kernel.org>