bankd_client_fsm: close IPA client connection before re-establishing it

ipa_client_conn_destroy() really only destroys the object, but not close
the underlying file descriptor.  This leads to old connections
lingering around, which in turn (in case of the remsim client) will
occupy banksim worker threads.

Change-Id: If87f4bbc133e4dc812fa96a75e8495bad65275aa
diff --git a/src/bankd_client_fsm.c b/src/bankd_client_fsm.c
index 8cc773a..cedb597 100644
--- a/src/bankd_client_fsm.c
+++ b/src/bankd_client_fsm.c
@@ -152,6 +152,7 @@
 	/* re-create bankd_conn */
 	if (bc->bankd_conn) {
 		LOGPFSML(fi, LOGL_INFO, "Destroying existing connection to bankd\n");
+		ipa_client_conn_close(bc->bankd_conn);
 		ipa_client_conn_destroy(bc->bankd_conn);
 		bc->bankd_conn = NULL;
 	}