We really want to have fastboot enabled by default to avoid an ugly
modeset during boot.

Currently we are enabling fastboot by default on gen9+ (Skylake and newer).
The intention is to enable it on older generations after it has seen more
testing on gen9+.

VLV and CHV devices are still being sold in stores today, as such it is
desirable to also enable fastboot by default on these now.

I've extensively tested fastboot=1 support on over 50 different
Bay- and Cherry-Trail devices. Testing DSI and eDP panels as well as
HDMI output (and even DP over Type-C on one device).

All 50 devices work fine with fastboot=1. On 2 devices their DSI panel
turns black as soon as the i915 driver loads when fastboot=0, so having
fastboot enabled is required for these 2 to work properly (for lack of
a better fix).
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190129142237.8684-1-hdegoede@redhat.com