Make Swift uses API_WORKERS

Keep the default to 1 instead of going wild, cause Swift really would
kill the VM if we let it go (and keeps the old behavior).

Change-Id: I7449c1bb485459169b8870c871b887cbab8be865
diff --git a/lib/swift b/lib/swift
index 50e2482..a8dfe77 100644
--- a/lib/swift
+++ b/lib/swift
@@ -269,7 +269,7 @@
     iniset ${swift_node_config} DEFAULT log_facility LOG_LOCAL${log_facility}
 
     iniuncomment ${swift_node_config} DEFAULT workers
-    iniset ${swift_node_config} DEFAULT workers 1
+    iniset ${swift_node_config} DEFAULT workers ${API_WORKERS:-1}
 
     iniuncomment ${swift_node_config} DEFAULT disable_fallocate
     iniset ${swift_node_config} DEFAULT disable_fallocate true