drm/i915/gvt: Enable irq initialization for BXT.

Initialize BXT irq handler as SKL/KBL.

v2: All supported platforms share the same irq ops and map.
    Remove the platform check by now and let is_supported_device()
    be the gate keeper.
Signed-off-by: Colin Xu <colin.xu@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

drivers/gpu/drm/i915/gvt/interrupt.c

@@ -581,7 +581,9 @@ static void gen8_init_irq(
 
 		SET_BIT_INFO(irq, 4, PRIMARY_C_FLIP_DONE, INTEL_GVT_IRQ_INFO_DE_PIPE_C);
 		SET_BIT_INFO(irq, 5, SPRITE_C_FLIP_DONE, INTEL_GVT_IRQ_INFO_DE_PIPE_C);
-	} else if (IS_SKYLAKE(gvt->dev_priv) || IS_KABYLAKE(gvt->dev_priv)) {
+	} else if (IS_SKYLAKE(gvt->dev_priv)
+			|| IS_KABYLAKE(gvt->dev_priv)
+			|| IS_BROXTON(gvt->dev_priv)) {
 		SET_BIT_INFO(irq, 25, AUX_CHANNEL_B, INTEL_GVT_IRQ_INFO_DE_PORT);
 		SET_BIT_INFO(irq, 26, AUX_CHANNEL_C, INTEL_GVT_IRQ_INFO_DE_PORT);
 		SET_BIT_INFO(irq, 27, AUX_CHANNEL_D, INTEL_GVT_IRQ_INFO_DE_PORT);
@@ -691,14 +693,8 @@ int intel_gvt_init_irq(struct intel_gvt *gvt)
 
 	gvt_dbg_core("init irq framework\n");
 
-	if (IS_BROADWELL(gvt->dev_priv) || IS_SKYLAKE(gvt->dev_priv)
-		|| IS_KABYLAKE(gvt->dev_priv)) {
 	irq->ops = &gen8_irq_ops;
 	irq->irq_map = gen8_irq_map;
-	} else {
-		WARN_ON(1);
-		return -ENODEV;
-	}
 
 	/* common event initialization */
 	init_events(irq);