drm/panel: simple: set bpc field for logic technologies displays

In case bpc is not set for a panel it then throws a WARN(). Add bpc to
the panels logictechno_lt170410_2whc and logictechno_lt161010_2nh.

Fixes: 5728fe7f ("drm/panel: simple: add display timings for logic technologies displays")
Signed-off-by: Aishwarya Kothari <aishwarya.kothari@toradex.com>
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220831141622.39605-1-francesco.dolcini@toradex.com