fix get_key call in api_dht_raw.
fix get_key call in api_dht_raw.

jvf/scalaris,scalaris-team/scalaris,scalaris-team/scalaris,jvf/scalaris,scalaris-team/scalaris,caijieming-baidu/scalaris,scalaris-team/scalaris,scalaris-team/scalaris,jvf/scalaris,caijieming-baidu/scalaris,scalaris-team/scalaris,jvf/scalaris,caijieming-baidu/scalaris,caijieming-baidu/scalaris,caijieming-baidu/scalaris,jvf/scalaris,caijieming-baidu/scalaris,jvf/scalaris,scalaris-team/scalaris,jvf/scalaris,caijieming-baidu/scalaris,scalaris-team/scalaris