media: venus: parser: Prepare parser for multiple invocations

Presently the hfi_parser has been called only once during driver
probe. To prepare the parser function to be called multiple times
from recovery we need to initialize few variables which are used
during parsing time.

Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Reviewed-by: Fritz Koenig <frkoenig@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>