drm/panel: tpo-td043mtea1: remove redundant assignment

Variable val is initialized to a value in a for-loop that is
never read and hence it is redundant. Remove it.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190817122124.29650-1-colin.king@canonical.com