patman: Support autolink when some series are archived

Archived series currently cause an error when autolink is attempted. Add
a check to avoid this.

Series-to: u-boot
Signed-off-by: Simon Glass <sjg@chromium.org>
Series-links: 1:458284

tools/patman/cser_helper.py

@@ -495,6 +495,10 @@ class CseriesHelper:
             # Get a list of links to fetch
             for svid, ser_id, version in max_vers:
                 svinfo = svdict[svid]
+
+                # Handle archived series
+                if ser_id not in sdict:
+                    continue
                 ser = sdict[ser_id]
 
                 pwc = self.get_pcommit_dict(svid)