cpufreq: qcom-cpufreq-hw: Fix uninitialized throttled_freq warning

Commit 6240aaad was supposed to drop the reference count to the OPP,
instead it avoided more stuff if the OPP isn't found. This isn't
entirely correct. We already have a frequency value available, we just
couldn't align it with an OPP in case of IS_ERR(opp).

Lets continue with updating thermal pressure, etc, even if we aren't
able to find an OPP here.

This fixes warning generated by the 'smatch' tool.

Fixes: 6240aaad

 ("cpufreq: qcom-hw: fix the opp entries refcounting")
Cc: v5.18+ <stable@vger.kernel.org> # v5.18+
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>