When slurmctld is cold-started use a random elan program id

to start with instead of always using 1, which is prone to 
collisions.

src/plugins/switch/elan/qsw.c

@@ -379,7 +379,8 @@ qsw_init(qsw_libstate_t oldstate)
 	if (oldstate)
 		_copy_libstate(new, oldstate);
 	else {
-		new->ls_prognum = QSW_PRG_START;
+		new->ls_prognum = QSW_PRG_START + 
+			(lrand48() % (QSW_PRG_END - QSW_PRG_START + 1));
 		new->step_ctx_list = list_create(_step_ctx_del);
 	}
 	qsw_internal_state = new;