Add option to set chap algorithms for iscsid for FIPS

The default CHAP algorithm for iscsid is md5, which is disallowed
under fips.  We will set the chap algorithm to "SHA3-256,SHA256",
which should work under all configurations.

Change-Id: Ide186fb53b3f9826ff602cb7fb797f245a15033a

lib/nova

@@ -315,6 +315,10 @@ EOF
             sudo systemctl daemon-reload
         fi
 
+        # set chap algorithms.  The default chap_algorithm is md5 which will
+        # not work under FIPS
+        iniset -sudo /etc/iscsi/iscsid.conf DEFAULT "node.session.auth.chap_algs" "SHA3-256,SHA256"
+
         # ensure that iscsid is started, even when disabled by default
         restart_service iscsid
     fi