drm/i915/adl_s: Configure DPLL for ADL-S

drm/i915/adl_s: Configure DPLL for ADL-S

Add changes for configuring DPLL for ADL-S
- Reusing DG1 DPLL 2 & DPLL 3 for ADL-S
- Extend CNL macro to choose DPLL_ENABLE
  for ADL-S.
- Select CFGCR0 and CFGCR1 for ADL-S plls.

On BSpec: 53720 PLL arrangement dig for adls:
DPLL2 cfgcr is programmed using _ADLS_DPLL3_CFGCR(0/1)
DPLL3 cfgcr is programmed using _ADLS_DPLL4_CFGCR(0/1)

v2 (Lucas): add missing update_ref_clks

Bspec: 50288
Bspec: 50289
Bspec: 49443

v3 : Adding another bit to HDPORT_DPLL_USED_MASK bitfield
for DPLL3_USED.(mdroper)

Bspec: 53707

v4:  BSpec 53723 has been updated with note - DPLL2 is
controlled by DPLL4 CFGCR 0/1.(mdroper)

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Aditya Swarup <aditya.swarup@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210125140753.347998-6-aditya.swarup@intel.com