opp: Put opp table in dev_pm_opp_set_rate() for empty tables

We get the opp_table pointer at the top of the function and so we should
put the pointer at the end of the function like all other exit paths
from this function do.

Cc: v5.7+ <stable@vger.kernel.org> # v5.7+
Fixes: aca48b61 ("opp: Manage empty OPP tables with clk handle")
Reviewed-by: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
[ Viresh: Split the patch into two ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>