We need to call of_node_put(node) on the error paths for this function.

Fixes: 53e2822e ("rpmsg: Introduce Qualcomm SMD backend")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200908071841.GA294938@mwandaSigned-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>