msm: camera: isp: Correct assignment of clock rates

If there is no change in CSID and TFE clock rates
then correctly assign current clock rates to local
varaibles.

CRs-Fixed: 2855742
Change-Id: Ibd71274ba7a7844c3841060eb3b3b14ba80ed4b0
Signed-off-by: Shravya Samala <shravyas@codeaurora.org>