drm: move i915_hdcp_interface.h under include/drm/intel

Clean up the top level include/drm directory by grouping all the Intel
specific files under a common subdirectory.

Cc: Daniel Vetter <[e-mail]>
Cc: Dave Airlie <[e-mail]>
Cc: Lucas De Marchi <[e-mail]>
Cc: Tomas Winkler <[e-mail]>
Acked-by: Lucas De Marchi <[e-mail]>
Acked-by: Rodrigo Vivi <[e-mail]>
Signed-off-by: Jani Nikula <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/5f5[e-mail]

drivers/gpu/drm/i915/display/intel_display_types.h

···
 #include <drm/drm_rect.h>
 #include <drm/drm_vblank.h>
 #include <drm/drm_vblank_work.h>
-#include <drm/i915_hdcp_interface.h>
+#include <drm/intel/i915_hdcp_interface.h>
 #include <media/cec-notifier.h>
 
 #include "i915_vma.h"

drivers/gpu/drm/i915/display/intel_hdcp_gsc.c

···
  * Copyright 2023, Intel Corporation.
  */
 
-#include <drm/i915_hdcp_interface.h>
+#include <drm/intel/i915_hdcp_interface.h>
 
 #include "gem/i915_gem_region.h"
 #include "gt/intel_gt.h"

drivers/gpu/drm/i915/display/intel_hdcp_gsc_message.c

···
  */
 
 #include <linux/err.h>
-#include <drm/i915_hdcp_interface.h>
+#include <drm/intel/i915_hdcp_interface.h>
 
 #include "i915_drv.h"
 #include "intel_hdcp_gsc_message.h"

drivers/gpu/drm/xe/display/xe_hdcp_gsc.c

···
  */
 
 #include <drm/drm_print.h>
-#include <drm/i915_hdcp_interface.h>
+#include <drm/intel/i915_hdcp_interface.h>
 #include <linux/delay.h>
 
 #include "abi/gsc_command_header_abi.h"

drivers/misc/mei/hdcp/mei_hdcp.c

···
 #include <linux/component.h>
 #include <drm/drm_connector.h>
 #include <drm/intel/i915_component.h>
-#include <drm/i915_hdcp_interface.h>
+#include <drm/intel/i915_hdcp_interface.h>
 
 #include "mei_hdcp.h"