dt-bindings: display: panel: Move flip properties to panel-common

The flip properties were used by "samsung,s6e8aa0.yaml" only so far. By
introducing "samsung,s6e88a0-ams427ap24.yaml" they become more common.

Signed-off-by: Jakob Hauser <jahau@rocketmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/e4edd8fc07b89006207f5f8962a816ff7f8f4601.1730070570.git.jahau@rocketmail.com


Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/e4edd8fc07b89006207f5f8962a816ff7f8f4601.1730070570.git.jahau@rocketmail.com