cpufreq: qcom: Fix qcom_cpufreq_hw_recalc_rate() to query LUT if LMh IRQ is not available

Currently, qcom_cpufreq_hw_recalc_rate() returns the LMh throttled
frequency for the domain even if LMh IRQ is not available. But as per
qcom_cpufreq_hw_get(), the driver has to query LUT entries to get the
actual frequency of the domain. So do the same in
qcom_cpufreq_hw_recalc_rate().

While doing so, refactor the existing qcom_cpufreq_hw_get() function so
that qcom_cpufreq_hw_recalc_rate() can make use of the existing code and
avoid code duplication. This also requires setting the
qcom_cpufreq_data::policy even if LMh IRQ is not available.

Fixes: 4370232c ("cpufreq: qcom-hw: Add CPU clock provider support")
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>