drm/i915: Add ERR_INT to gen7 error state

ERR_INT can generate interrupts. However since most of the conditions seem
quite fatal the patch opts to simply report it in error state instead of
adding more complexity to the interrupt handler for little gain (the
bits are sticky anyway).

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Antti Koskipaa <antti.koskipaa@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_drv.h

@@ -196,6 +196,7 @@ struct drm_i915_error_state {
 	u32 cpu_ring_head[I915_NUM_RINGS];
 	u32 cpu_ring_tail[I915_NUM_RINGS];
 	u32 error; /* gen6+ */
+	u32 err_int; /* gen7 */
 	u32 instpm[I915_NUM_RINGS];
 	u32 instps[I915_NUM_RINGS];
 	u32 instdone1;