drm/i915/display: move vbt check to intel_ddi_init()

Since commit 45c0673a ("drm/i915/bios: start using the
intel_bios_encoder_data directly") we lookup the devdata for each port
in intel_ddi_init() and just return if the port is not present in VBT
(or if we didn't create a fake devdata for it if VBT is not available).

So in intel_display.c we don't have to check
intel_bios_is_port_present(), just rely on the check in
intel_ddi_init().

v2: Rebase on commit 45c0673a ("drm/i915/bios: start using the
intel_bios_encoder_data directly") re-using that check in intel_ddi_init()
instead of adding a new one.

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210430223808.1078010-2-lucas.demarchi@intel.com