drm/client: fix kernel-doc warning in drm_client.h

scripts/kernel-doc complains about the comment for hotplug_failed,
so fix it:

include/drm/drm_client.h:111: warning: Incorrect use of kernel-doc format:          * @hotplug failed:

Fixes: 6a9d5ad ("drm/client: Add hotplug_failed flag")
Signed-off-by: Randy Dunlap <[email protected]>
Cc: Thomas Zimmermann <[email protected]>
Cc: Maarten Lankhorst <[email protected]>
Cc: Maxime Ripard <[email protected]>
Cc: Javier Martinez Canillas <[email protected]>
Cc: David Airlie <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: [email protected]
Signed-off-by: Thomas Zimmermann <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

Author: rddunlap

include/drm/drm_client.h

@@ -108,7 +108,7 @@ struct drm_client_dev {
 	struct drm_mode_set *modesets;
 
 	/**
-	 * @hotplug failed:
+	 * @hotplug_failed:
 	 *
 	 * Set by client hotplug helpers if the hotplugging failed
 	 * before. It is usually not tried again.