drm/i915: Call hsw_fdi_link_train() directly()

Remove the pointless vfunc detour for hsw_fdi_link_train()
and just call it directly. Also pass the encoder in so we
can nuke the silly encoder loop within.

Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191213195217.15168-1-ville.syrjala@linux.intel.com


Reviewed-by: José Roberto de Souza <jose.souza@intel.com>