video: fbdev: nvidia: Remove extra return

Minor cleanup to remove extra return statement.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Sabyasachi Gupta <sabyasachi.linux@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1562781795-3494-1-git-send-email-jrdr.linux@gmail.com