drm/i915/cdclk: Rename intel_cdclk_needs_modeset to intel_cdclk_clock_changed

Looks like the name and description of intel_cdclk_needs_modeset()
became inaccurate as of commit 59f9e9ca ("drm/i915: Skip modeset for
cdclk changes if possible"), when it became possible to update the cdclk
without requiring disabling the pipes when only changing the cd2x
divider was enough.

Later on we also added the same type of support with squash and crawling
with commit 25e0e5ae ("drm/i915/display: Do both crawl and squash
when changing cdclk"), commit d4a23930 ("drm/i915: Allow cdclk
squasher to be reconfigured live") and commit d62686ba
("drm/i915/adl_p: CDCLK crawl support for ADL").

As such, update that function's name and documentation to something more
appropriate, since the real checks for requiring modeset are done
elsewhere.

v2:
  - Rename to intel_cdclk_clock_changed instead of
    intel_cdclk_params_changed. (Ville)

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240214202719.298407-2-gustavo.sousa@intel.com