download-drivers: compare BIOS versions numerically, not as strings

parse_bios_catalog kept the 'latest' BIOS per model with a string compare, so e.g. '1.20.1' > '1.9.0' was False and it wrongly retained the older 1.9.0. Added _ver_tuple() and compare tuples of ints so the genuinely newest firmware wins.

scripts/download-drivers.py

@@ -155,6 +155,14 @@ def parse_driver_catalog(xml_path, os_filter=None):
     return packs
 
 
+def _ver_tuple(v):
+    """Version string -> tuple of ints for numeric compare ('1.20.1' -> (1,20,1))."""
+    try:
+        return tuple(int(x) for x in str(v).split("."))
+    except (ValueError, AttributeError):
+        return (0,)
+
+
 def parse_bios_catalog(xml_path, model_names):
     """Parse DellSDPCatalogPC.xml → list of latest BIOS update dicts for given models."""
     tree = ET.parse(xml_path)
@@ -199,9 +207,11 @@ def parse_bios_catalog(xml_path, model_names):
             "model": matched_model,
         }
 
-        # Keep latest version per model
+        # Keep latest version per model. Compare numerically (tuple of ints),
+        # not as strings - "1.20.1" > "1.9.0" is False as a string compare,
+        # which would wrongly keep the older 1.9.0 BIOS.
         key = matched_model
-        if key not in bios or version > bios[key]["version"]:
+        if key not in bios or _ver_tuple(version) > _ver_tuple(bios[key]["version"]):
             bios[key] = entry
 
     return list(bios.values())