clk: delete a local variable's repeated assignment

It's the same to the next statement, "ret = clk->parent". I think compiler will
optimize it, it's just not looking well.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 4896ae9..5307225 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1614,7 +1614,7 @@
 
 	if (clk->num_parents == 1) {
 		if (IS_ERR_OR_NULL(clk->parent))
-			ret = clk->parent = __clk_lookup(clk->parent_names[0]);
+			clk->parent = __clk_lookup(clk->parent_names[0]);
 		ret = clk->parent;
 		goto out;
 	}