drm/rcar-du: Fix error check when retrieving crtc state

drm_atomic_get_crtc_state() returns an error pointer when it fails, so
the null check is doing nothing here.

Credit to 0-day/Dan Carpenter for reporting this.

Fixes: 6f3b62781bbd ("drm: Convert connector_helper_funcs->atomic_check to accept drm_atomic_state")
Cc: Daniel Vetter <[email protected]>
Cc: Ville Syrjälä <[email protected]>
Cc: Jani Nikula <[email protected]>
Cc: Joonas Lahtinen <[email protected]>
Cc: Rodrigo Vivi <[email protected]>
Cc: Ben Skeggs <[email protected]>
Cc: Laurent Pinchart <[email protected]>
Cc: Kieran Bingham <[email protected]>
Cc: Eric Anholt <[email protected]>
Cc: Laurent Pinchart <[email protected]> [for rcar lvds]
Cc: Sean Paul <[email protected]>
Cc: Maarten Lankhorst <[email protected]>
Cc: Maxime Ripard <[email protected]>
Cc: Sean Paul <[email protected]>
Cc: David Airlie <[email protected]>
Cc: Lyude Paul <[email protected]>
Cc: Karol Herbst <[email protected]>
Cc: Ilia Mirkin <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Reported-by: kbuild test robot <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
Reviewed-by: Laurent Pinchart <[email protected]>
Signed-off-by: Sean Paul <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

0 files changed, 0 insertions, 0 deletions