clk: versatile: Add of_node_put() before return statement

Every iteration of for_each_available_child_of_node() decrements
the reference count of the previous node, however when control is
transferred from the middle of the loop, as in the case of a return
or break or goto, there is no decrement thus ultimately resulting in
a memory leak.

Fix a potential memory leak in clk-impd1.c by inserting
of_node_put() before a return statement.

Issue found with Coccinelle.

Signed-off-by: Sumera Priyadarsini <sylphrenadin@gmail.com>
Link: https://lore.kernel.org/r/20200829175704.GA10998@Kaladin
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>