manifest: Fix compilation warnings in hostap

Hotfix for two compilation warning issues for
wpa_drv_zep_event_dfs_cac_finished() and
wpa_drv_zep_event_dfs_cac_started(),
and for hmac_prf256() in hostap project.

Signed-off-by: Jukka Rissanen <jukka.rissanen@nordicsemi.no>