scsi: ufs: exynos: Allow UFS Gear 4

UFS Gear 4 offers faster speeds, and better power usage so lets enable
it.

Currently ufshcd_init_host_params() sets UFS_HS_G3 as a default, so even
if the device supports G4 we end up negotiating down to G3.

For SoCs like gs101 which have a UFS major controller version of 3 or
above advertise Gear 4. This then allows a Gear 4 link on Pixel 6.

For earlier controller versions keep the current default behaviour of
reporting G3.

Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Link: https://lore.kernel.org/r/20241031150033.3440894-4-peter.griffin@linaro.org


Reviewed-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>