rdma: memory leak RDMAContext::host

It is allocated by g_strdup(), so needs to be freed.

Reviewed-by: Michael R. Hines <mrhines@us.ibm.com>
Signed-off-by: Isaku Yamahata <yamahata@private.email.ne.jp>
Signed-off-by: Michael R. Hines <mrhines@us.ibm.com>
Message-id: 1375584894-9917-8-git-send-email-mrhines@linux.vnet.ibm.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
