Currently, board code needs to call habv4_get_status() explicitely, but
there is no reason that it cannot be called automatically at startup
when HABv4 is enabled. This way the call cannot be forgotten and we can
make sure to report all potentially occuring HAB warnings and errors.

Signed-off-by: Roland Hieber <r.hieber@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>