drm/bridge: it6505: fix HDCP encryption when R0 ready

When starting HDCP authentication, HDCP encryption should be enabled
when R0'is checked.

Change encryption enables time at R0' ready.
The hardware HDCP engine trigger is changed and the repeater KSV fails
will restart HDCP.

Signed-off-by: Hermes Wu <hermes.wu@ite.com.tw>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20241230-v7-upstream-v7-6-e0fdd4844703@ite.corp-partner.google.com