drm/sched: Return an error code only as a constant in drm_sched_init()

Return an error code without storing it in an intermediate variable.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Link: https://patchwork.freedesktop.org/patch/msgid/85f8004e-f0c9-42d9-8c59-30f1b4e0b89e@web.de


Reviewed-by: Luben Tuikov <ltuikov89@gmail.com>
Signed-off-by: Luben Tuikov <ltuikov89@gmail.com>