drm/i915/crc: Make IPS workaround generic

Other features like PSR2 also needs to be disabled while getting CRC
so lets rename ips_force_disable to crc_enabled, drop all this checks
for pipe A and HSW and BDW and make it generic and
hsw_compute_ips_config() will take care of all the checks removed
from here.

v2: Renaming and parameter changes to the functions that prepares the
commit (Ville)

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190308000050.6226-5-jose.souza@intel.com