Don't stop parsing layer on fatal error in update script

"Fatal" errors during parsing a single recipe (such as finding legacy
staging) shouldn't stop us from parsing the rest of the layer. To do
this we need to catch BaseException instead of Exception as fatal errors
end up calling sys.exit.

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>

layerindex/update.py

@@ -95,7 +95,9 @@ def update_recipe_file(data, path, recipe):
         recipe.section = envdata.getVar("SECTION", True)
         recipe.license = envdata.getVar("LICENSE", True)
         recipe.homepage = envdata.getVar("HOMEPAGE", True)
-    except Exception as e:
+    except KeyboardInterrupt:
+        raise
+    except BaseException as e:
         logger.info("Unable to read %s: %s", fn, str(e))
 
 def update_machine_conf_file(path, machine):