ARM: OMAP2+: Fix refcount leak in omap_gic_of_init

The of_find_compatible_node() function returns a node pointer with
refcount incremented, We should use of_node_put() on it when done
Add the missing of_node_put() to release the refcount.

Fixes: fd1c0786 ("ARM: OMAP4: Fix the init code to have OMAP4460 errata available in DT build")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Message-Id: <20220309104302.18398-1-linmq006@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>