clk: mediatek: mux: Reverse check for existing clk to reduce nesting level

The clk registration code here currently does:

    if (IS_ERR_OR_NULL(clk_data->clks[mux->id])) {
            ... do clk registration ...
    }

This extra level of nesting wastes screen real estate.

Reduce the nesting level by reversing the conditional shown above.
Other than that, functionality is not changed.

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/20220208124034.414635-24-wenst@chromium.org
Reviewed-by: Chun-Jie Chen <chun-jie.chen@mediatek.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

Author: wens

drivers/clk/mediatek/clk-mux.c

@@ -208,16 +208,17 @@ int mtk_clk_register_muxes(const struct mtk_mux *muxes,
 	for (i = 0; i < num; i++) {
 		const struct mtk_mux *mux = &muxes[i];
 
-		if (IS_ERR_OR_NULL(clk_data->clks[mux->id])) {
-			clk = mtk_clk_register_mux(mux, regmap, lock);
+		if (!IS_ERR_OR_NULL(clk_data->clks[mux->id]))
+			continue;
 
-			if (IS_ERR(clk)) {
-				pr_err("Failed to register clk %s: %pe\n", mux->name, clk);
-				continue;
-			}
+		clk = mtk_clk_register_mux(mux, regmap, lock);
 
-			clk_data->clks[mux->id] = clk;
+		if (IS_ERR(clk)) {
+			pr_err("Failed to register clk %s: %pe\n", mux->name, clk);
+			continue;
 		}
+
+		clk_data->clks[mux->id] = clk;
 	}
 
 	return 0;