scsi: ufs: ufs-exynos: Fix static checker warning

scsi: ufs: ufs-exynos: Fix static checker warning

clk_get_rate() returns unsigned long and currently this driver stores the
return value in u32 type, resulting the below warning:

Fixed smatch warnings:

        drivers/scsi/ufs/ufs-exynos.c:286 exynos_ufs_get_clk_info()
        warn: wrong type for 'ufs->mclk_rate' (should be 'ulong')

        drivers/scsi/ufs/ufs-exynos.c:287 exynos_ufs_get_clk_info()
        warn: wrong type for 'pclk_rate' (should be 'ulong')

Link: https://lore.kernel.org/r/20210819171131.55912-1-alim.akhtar@samsung.com
Fixes: 55f4b1f73631 ("scsi: ufs: ufs-exynos: Add UFS host support for Exynos SoCs")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>