init: add missing submodule arg

The submodule argument to Sync_LocalHalf was missing in
MetaBranchSwitch, causing submodules not to get synced when the
-b/--manifest-branch argument to init is used.

Change-Id: Ie86d271abac2020725770be36ead83be3326e64b
Signed-off-by: Martin Kelly <mkelly@xevo.com>
diff --git a/subcmds/init.py b/subcmds/init.py
index 65dfd1f..46cdd23 100644
--- a/subcmds/init.py
+++ b/subcmds/init.py
@@ -256,7 +256,7 @@
       sys.exit(1)
 
     if opt.manifest_branch:
-      m.MetaBranchSwitch()
+      m.MetaBranchSwitch(submodules=opt.submodules)
 
     syncbuf = SyncBuffer(m.config)
     m.Sync_LocalHalf(syncbuf, submodules=opt.submodules)