drm: Update docs after moving DisplayPort helpers around

DRM's DisplayPort helpers moved into the subdirectory dp/. Change
the documentation accordingly.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: adb9d5a2 ("drm/dp: Move DisplayPort helpers into separate helper module")
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reported-by: Jani Nikula <jani.nikula@linux.intel.com>
Tested-by: Jani Nikula <jani.nikula@intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: dri-devel@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220120113647.22484-1-tzimmermann@suse.de

Documentation/gpu/drm-kms-helpers.rst

@@ -232,34 +232,34 @@ HDCP Helper Functions Reference
 Display Port Helper Functions Reference
 =======================================
 
-.. kernel-doc:: drivers/gpu/drm/drm_dp_helper.c
+.. kernel-doc:: drivers/gpu/drm/dp/drm_dp.c
    :doc: dp helpers
 
-.. kernel-doc:: include/drm/drm_dp_helper.h
+.. kernel-doc:: include/drm/dp/drm_dp_helper.h
    :internal:
 
-.. kernel-doc:: drivers/gpu/drm/drm_dp_helper.c
+.. kernel-doc:: drivers/gpu/drm/dp/drm_dp.c
    :export:
 
 Display Port CEC Helper Functions Reference
 ===========================================
 
-.. kernel-doc:: drivers/gpu/drm/drm_dp_cec.c
+.. kernel-doc:: drivers/gpu/drm/dp/drm_dp_cec.c
    :doc: dp cec helpers
 
-.. kernel-doc:: drivers/gpu/drm/drm_dp_cec.c
+.. kernel-doc:: drivers/gpu/drm/dp/drm_dp_cec.c
    :export:
 
 Display Port Dual Mode Adaptor Helper Functions Reference
 =========================================================
 
-.. kernel-doc:: drivers/gpu/drm/drm_dp_dual_mode_helper.c
+.. kernel-doc:: drivers/gpu/drm/dp/drm_dp_dual_mode_helper.c
    :doc: dp dual mode helpers
 
-.. kernel-doc:: include/drm/drm_dp_dual_mode_helper.h
+.. kernel-doc:: include/drm/dp/drm_dp_dual_mode_helper.h
    :internal:
 
-.. kernel-doc:: drivers/gpu/drm/drm_dp_dual_mode_helper.c
+.. kernel-doc:: drivers/gpu/drm/dp/drm_dp_dual_mode_helper.c
    :export:
 
 Display Port MST Helpers
@@ -268,19 +268,19 @@ Display Port MST Helpers
 Overview
 --------
 
-.. kernel-doc:: drivers/gpu/drm/drm_dp_mst_topology.c
+.. kernel-doc:: drivers/gpu/drm/dp/drm_dp_mst_topology.c
    :doc: dp mst helper
 
-.. kernel-doc:: drivers/gpu/drm/drm_dp_mst_topology.c
+.. kernel-doc:: drivers/gpu/drm/dp/drm_dp_mst_topology.c
    :doc: Branch device and port refcounting
 
 Functions Reference
 -------------------
 
-.. kernel-doc:: include/drm/drm_dp_mst_helper.h
+.. kernel-doc:: include/drm/dp/drm_dp_mst_helper.h
    :internal:
 
-.. kernel-doc:: drivers/gpu/drm/drm_dp_mst_topology.c
+.. kernel-doc:: drivers/gpu/drm/dp/drm_dp_mst_topology.c
    :export:
 
 Topology Lifetime Internals
@@ -289,7 +289,7 @@ Topology Lifetime Internals
 These functions aren't exported to drivers, but are documented here to help make
 the MST topology helpers easier to understand
 
-.. kernel-doc:: drivers/gpu/drm/drm_dp_mst_topology.c
+.. kernel-doc:: drivers/gpu/drm/dp/drm_dp_mst_topology.c
    :functions: drm_dp_mst_topology_try_get_mstb drm_dp_mst_topology_get_mstb
                drm_dp_mst_topology_put_mstb
                drm_dp_mst_topology_try_get_port drm_dp_mst_topology_get_port