clk: tegra20: Fix refcount leak in tegra20_clock_init

of_find_matching_node() returns a node pointer with refcount
incremented, we should use of_node_put() on it when not need anymore.
Add missing of_node_put() to avoid refcount leak.

Fixes: 37c26a90

 ("clk: tegra: add clock support for Tegra20")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220523152811.19692-1-linmq006@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>