lisa.wa: Add a wa_path column to the dataframes
lisa.wa: Add a wa_path column to the dataframes

Add a wa_path column to the dataframes so that we can correctly
discriminate between data comming from different folders, even if they
share the same set of tags (e.g. iteration might not be enough if the
output was done with separate invocations of WA).

ARM-software/lisa,credp/lisa,ARM-software/lisa,credp/lisa,credp/lisa,credp/lisa,ARM-software/lisa,ARM-software/lisa