cpufreq: Add QCS8300 to cpufreq-dt-platdev blocklist

cpufreq: Add QCS8300 to cpufreq-dt-platdev blocklist

The Qualcomm QCS8300 platform uses the qcom-cpufreq-hw
driver, so add it to the cpufreq-dt-platdev driver's blocklist.

Signed-off-by: Faruque Ansari <faruque.ansari@oss.qualcomm.com>
Reviewed-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>