media: allegro: fix log2_max_poc in firmware 2019.1

media: allegro: fix log2_max_poc in firmware 2019.1

The log2_max_poc field is used to set log2_max_pic_order_cnt_lsb_minus4
for the coded stream. It has an allowed range of 0 to 12.

param contains the value without the minus4, but since firmware
version 2019.1, the value has to be log2_max_pic_order_cnt_lsb - 1,
presumably to fit the maximum value of 16 into a 4 bit field.

The driver does not support firmware version 2019.1. Thus, change the
behaviour starting from firmware version 2019.2.

Signed-off-by: Michael Tretter <m.tretter@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>