drm/i915/display: Remove compile guard around fbdev debugfs output

If fbdev support has been disabled, no output will be shown. Remove
the fbdev-related compile guard from the driver's debugfs code.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241212170913.185939-12-tzimmermann@suse.de


Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>