ufs: tegra: Enable and Disable mphy_force_ls_mode.

ufs: tegra: Enable and Disable mphy_force_ls_mode.

-Enable and Disable mphy_force_ls_mode to keep clocks
in default state.

Bug 200278112

Change-Id: Icc7a61d39976f48873694a5d61eec62a14271ee2
Signed-off-by: Naveen Kumar Arepalli <naveenk@nvidia.com>
Reviewed-on: http://git-master/r/1478096
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: Sachin Nikam <snikam@nvidia.com>
Reviewed-by: Pavan Kunapuli <pkunapuli@nvidia.com>
Reviewed-by: Venu Byravarasu <vbyravarasu@nvidia.com>