drm/mediatek/dp: fix memory leak on ->get_edid callback error path

stable inclusion
from stable-v6.6.3
commit 4aa9db1eab76654aedbebe49d336bf6bc8b397d6
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8LBQP

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=4aa9db1eab76654aedbebe49d336bf6bc8b397d6



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commit fcaf9761fd5884a64eaac48536f8c27ecfd2e6bc upstream.

Setting new_edid to NULL leaks the buffer.

Fixes: f70ac097 ("drm/mediatek: Add MT8195 Embedded DisplayPort driver")
Cc: Markus Schneider-Pargmann <msp@baylibre.com>
Cc: Guillaume Ranquet <granquet@baylibre.com>
Cc: Bo-Chen Chen <rex-bc.chen@mediatek.com>
Cc: CK Hu <ck.hu@mediatek.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Cc: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: <stable@vger.kernel.org> # v6.1+
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Guillaume Ranquet <granquet@baylibre.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20230914131058.2472260-1-jani.nikula@intel.com/


Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>