drm/i915: don't enumerate HDMID if an eDP panel is already active on the port

This prevents the HDMI detect functions from poking at an eDP
connected panel, which can lead to trouble.

[danvet: Note that we have some other reports of DP vs. HDMI fighting,
but the general case is a much bigger fish to fry.]

References: https://bugs.freedesktop.org/show_bug.cgi?id=42278
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -6558,7 +6558,7 @@ static void intel_setup_outputs(struct drm_device *dev)
 		if (I915_READ(HDMIC) & PORT_DETECTED)
 			intel_hdmi_init(dev, HDMIC);
 
-		if (I915_READ(HDMID) & PORT_DETECTED)
+		if (!dpd_is_edp && I915_READ(HDMID) & PORT_DETECTED)
 			intel_hdmi_init(dev, HDMID);
 
 		if (I915_READ(PCH_DP_C) & DP_DETECTED)