drm/i915: Drop redundant shared_dpll=NULL assignments

The crtc state is expected to be fully cleared before readout,
so there is no need to clear the shared_dpll pointers by hand.

Reviewed-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250306163420.3961-2-ville.syrjala@linux.intel.com

Author: vsyrjala

drivers/gpu/drm/i915/display/intel_display.c

@@ -2997,7 +2997,6 @@ static bool i9xx_get_pipe_config(struct intel_crtc *crtc,
 	pipe_config->output_format = INTEL_OUTPUT_FORMAT_RGB;
 	pipe_config->sink_format = pipe_config->output_format;
 	pipe_config->cpu_transcoder = (enum transcoder) crtc->pipe;
-	pipe_config->shared_dpll = NULL;
 
 	ret = false;
 
@@ -3339,7 +3338,6 @@ static bool ilk_get_pipe_config(struct intel_crtc *crtc,
 		return false;
 
 	pipe_config->cpu_transcoder = (enum transcoder) crtc->pipe;
-	pipe_config->shared_dpll = NULL;
 
 	ret = false;
 	tmp = intel_de_read(display,
@@ -3906,8 +3904,6 @@ static bool hsw_get_pipe_config(struct intel_crtc *crtc,
 						       POWER_DOMAIN_PIPE(crtc->pipe)))
 		return false;
 
-	pipe_config->shared_dpll = NULL;
-
 	active = hsw_get_transcoder_state(crtc, pipe_config, &crtc->hw_readout_power_domains);
 
 	if ((display->platform.geminilake || display->platform.broxton) &&