cpufreq: zynq: Fix refcount leak in zynq_get_revision

of_find_compatible_node() returns a node pointer with refcount
incremented, we should use of_node_put() on it when done.
Add missing of_node_put() to avoid refcount leak.

Fixes: 00f7dc63

 ("ARM: zynq: Add support for SOC_BUS")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220605082807.21526-1-linmq006@gmail.com


Signed-off-by: Michal Simek <michal.simek@amd.com>