CVE-2025-37830 cpufreq: scmi: Fix null-ptr-deref in scmi_cpufreq_get_rate()

In the Linux kernel, the following vulnerability has been resolved: cpufreq: scmi: Fix null-ptr-deref in scmicpufreqgetrate cpufreqcpugetraw can return NULL when the target CPU is not present in the policy-cpus mask. scmicpufreqgetrate does not check for this case, which results in a NULL pointer...