clk: Remove unneeded NULL checks

As clk_unprepare_unused_subtree and clk_disable_unused_subtree are
always called with a valid struct clk.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>

drivers/clk/clk.c

@@ -428,9 +428,6 @@ static void clk_unprepare_unused_subtree(struct clk *clk)
 {
 	struct clk *child;
 
-	if (!clk)
-		return;
-
 	hlist_for_each_entry(child, &clk->children, child_node)
 		clk_unprepare_unused_subtree(child);
 
@@ -454,9 +451,6 @@ static void clk_disable_unused_subtree(struct clk *clk)
 	struct clk *child;
 	unsigned long flags;
 
-	if (!clk)
-		goto out;
-
 	hlist_for_each_entry(child, &clk->children, child_node)
 		clk_disable_unused_subtree(child);
 
@@ -482,9 +476,6 @@ static void clk_disable_unused_subtree(struct clk *clk)
 
 unlock_out:
 	clk_enable_unlock(flags);
-
-out:
-	return;
 }
 
 static bool clk_ignore_unused;