The device info offset arrays for unevenly spaced register offsets is
great for widely used registers. However, the palette registers are only
used in one function, i9xx_load_luts_internal(), and only for GMCH
platforms, wasting device info. Replace palette_offsets with _PICK() in
palette register definition.

While the use of _PICK() does not check for pipe C existence, neither
does the current offset array usage, and leads to bogus address when
pipe C is passed to PALETTE() on non-CHV. Using _PICK() at least leads
to a sensible register offset, just non-existing on non-CHV. Either way,
this shouldn't happen anyway.

Remove unused old palette macros while at it.

Bloat-o-meter results below for completeness.

add/remove: 0/0 grow/shrink: 3/6 up/down: 94/-278 (-184)
Function                                     old     new   delta
i9xx_load_luts_internal                      394     483     +89
i915_driver_load                            5103    5107      +4
g4x_pre_enable_dp                            378     379      +1
intel_engines_init_mmio                     1117    1116      -1
intel_engine_lookup_user                      47      46      -1
hdmi_port_clock_valid                        310     309      -1
gen11_irq_handler                            707     706      -1
intel_device_info_dump_runtime               329     311     -18
intel_device_info_runtime_init              5166    4910    -256
Total: Before=918650, After=918466, chg -0.02%

add/remove: 0/0 grow/shrink: 0/48 up/down: 0/-576 (-576)
Data                                         old     new   delta
intel_valleyview_info                        200     188     -12
intel_skylake_gt4_info                       200     188     -12
intel_skylake_gt3_info                       200     188     -12
intel_skylake_gt2_info                       200     188     -12
intel_skylake_gt1_info                       200     188     -12
intel_sandybridge_m_gt2_info                 200     188     -12
intel_sandybridge_m_gt1_info                 200     188     -12
intel_sandybridge_d_gt2_info                 200     188     -12
intel_sandybridge_d_gt1_info                 200     188     -12
intel_pineview_info                          200     188     -12
intel_kabylake_gt3_info                      200     188     -12
intel_kabylake_gt2_info                      200     188     -12
intel_kabylake_gt1_info                      200     188     -12
intel_ivybridge_q_info                       200     188     -12
intel_ivybridge_m_gt2_info                   200     188     -12
intel_ivybridge_m_gt1_info                   200     188     -12
intel_ivybridge_d_gt2_info                   200     188     -12
intel_ivybridge_d_gt1_info                   200     188     -12
intel_ironlake_m_info                        200     188     -12
intel_ironlake_d_info                        200     188     -12
intel_icelake_11_info                        200     188     -12
intel_i965gm_info                            200     188     -12
intel_i965g_info                             200     188     -12
intel_i945gm_info                            200     188     -12
intel_i945g_info                             200     188     -12
intel_i915gm_info                            200     188     -12
intel_i915g_info                             200     188     -12
intel_i865g_info                             200     188     -12
intel_i85x_info                              200     188     -12
intel_i845g_info                             200     188     -12
intel_i830_info                              200     188     -12
intel_haswell_gt3_info                       200     188     -12
intel_haswell_gt2_info                       200     188     -12
intel_haswell_gt1_info                       200     188     -12
intel_gm45_info                              200     188     -12
intel_geminilake_info                        200     188     -12
intel_g45_info                               200     188     -12
intel_g33_info                               200     188     -12
intel_coffeelake_gt3_info                    200     188     -12
intel_coffeelake_gt2_info                    200     188     -12
intel_coffeelake_gt1_info                    200     188     -12
intel_cherryview_info                        200     188     -12
intel_cannonlake_info                        200     188     -12
intel_broxton_info                           200     188     -12
intel_broadwell_rsvd_info                    200     188     -12
intel_broadwell_gt3_info                     200     188     -12
intel_broadwell_gt2_info                     200     188     -12
intel_broadwell_gt1_info                     200     188     -12
Total: Before=195529, After=194953, chg -0.29%

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181031110453.12722-1-jani.nikula@intel.com