drm: IRQ midlayer is now legacy

Hide the DRM midlayer behind CONFIG_DRM_LEGACY, make functions use
the prefix drm_legacy_, and move declarations to drm_legacy.h.
In struct drm_device, move the fields irq and irq_enabled behind
CONFIG_DRM_LEGACY.

All callers have been updated.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210803090704.32152-15-tzimmermann@suse.de
diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h
index f588f96..604b1d1 100644
--- a/include/drm/drm_device.h
+++ b/include/drm/drm_device.h
@@ -192,20 +192,6 @@ struct drm_device {
 	struct list_head clientlist;
 
 	/**
-	 * @irq_enabled:
-	 *
-	 * Indicates that interrupt handling is enabled, specifically vblank
-	 * handling. Drivers which don't use drm_irq_install() need to set this
-	 * to true manually.
-	 */
-	bool irq_enabled;
-
-	/**
-	 * @irq: Used by the drm_irq_install() and drm_irq_unistall() helpers.
-	 */
-	int irq;
-
-	/**
 	 * @vblank_disable_immediate:
 	 *
 	 * If true, vblank interrupt will be disabled immediately when the
@@ -372,6 +358,10 @@ struct drm_device {
 
 	/* Scatter gather memory */
 	struct drm_sg_mem *sg;
+
+	/* IRQs */
+	bool irq_enabled;
+	int irq;
 #endif
 };