feat: add cpu scaling for rpi

This PR ensures we support scaling CPU on the rpi. Results in 3x the amount of CPU events processed each second!

Signed-off-by: Spencer Smith <robertspencersmith@gmail.com>
(cherry picked from commit 7a89c26)

kernel/kernel/config-arm64

@@ -581,7 +581,7 @@ CONFIG_ARM_BRCMSTB_AVS_CPUFREQ=y
 CONFIG_ARM_IMX_CPUFREQ_DT=y
 # CONFIG_ARM_MEDIATEK_CPUFREQ is not set
 CONFIG_ARM_QCOM_CPUFREQ_HW=y
-# CONFIG_ARM_RASPBERRYPI_CPUFREQ is not set
+CONFIG_ARM_RASPBERRYPI_CPUFREQ=y
 CONFIG_ARM_SCMI_CPUFREQ=y
 CONFIG_QORIQ_CPUFREQ=y
 # end of CPU Frequency scaling