intelfb: add vsync interrupt support

[05/05] intelfb: Honor FB_ACTIVATE_VBL for display panning

Extends the intelfb_vsync struct to store panning offset. The interrupt service routine uses the stored panning offset if a pan is requested for the vsync. intelfbhw_disable_irq also pans the display if there is a pending request.

Signed-off-by: Eric Hustvedt <ehustvedt@cecropia.com>
diff --git a/drivers/video/intelfb/intelfb.h b/drivers/video/intelfb/intelfb.h
index 65ac370..abd4c56 100644
--- a/drivers/video/intelfb/intelfb.h
+++ b/drivers/video/intelfb/intelfb.h
@@ -211,6 +211,8 @@
 struct intelfb_vsync {
 	wait_queue_head_t wait;
 	unsigned int count;
+	int pan_display;
+	u32 pan_offset;
 };
 
 struct intelfb_info {