scsi: ufs: core: Add a vop to map clock frequency to gear speed

scsi: ufs: core: Add a vop to map clock frequency to gear speed

Add a vop to map UFS host controller clock frequencies to the corresponding
maximum supported UFS high speed gear speeds. During clock scaling, we can
map the target clock frequency, demanded by devfreq, to the maximum
supported gear speed, so that devfreq can scale the gear to the highest
gear speed supported at the target clock frequency, instead of just scaling
up/down the gear between the min and max gear speeds.

Co-developed-by: Ziqi Chen <quic_ziqichen@quicinc.com>
Signed-off-by: Ziqi Chen <quic_ziqichen@quicinc.com>
Signed-off-by: Can Guo <quic_cang@quicinc.com>
Link: https://lore.kernel.org/r/20250213080008.2984807-4-quic_ziqichen@quicinc.com
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>