drm/bridge: lt9611: disable hpd for lower firmware version

The firmware version which less than 0x40 did not support hpd,
so do not enable hpd for it.

Change-Id: Ic3567b42834fe060e494f859f007e7dc3657e7b7
Signed-off-by: Yuan Zhao <yzhao@codeaurora.org>