drm/radeon/kms: adjust quirk for acer laptop

Acer laptop (TravelMate 5730G) has an HDMI connector
on the laptop and a DVI connector on the docking station
and both share the same encoder, hpd pin, and ddc line.
The bios connector table reflects this and is technically
correct, however, we drop the DVI connector here since
xrandr has no concept of encoders (only crtcs and connectors)
and will try and drive both connectors with different crtcs
which isn't possible on the hardware side and leaves no crtcs
for LVDS or VGA.

Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=32732

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>