drm/i915/ltphy: Program LT Phy Non-TBT PLL disable sequence

drm/i915/ltphy: Program LT Phy Non-TBT PLL disable sequence

Program in the steps for Non TBT PLL disable sequence.
The whole function can be defined in one shot since most of
prequiste functions are already coded in.

Bspec: 74492
Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Arun R Murthy <arun.r.murthy@intel.com>
Link: https://patch.msgid.link/20251101032513.4171255-17-suraj.kandpal@intel.com