sstate: Ensure siginfo and sig files are also touched
Maintaining an sstate mirror is complicated at the moment as only the main
sstate tgz files have their timestamp updated when they're used.
This causes problems as the siginfo files can be removed from the server
due to inactivity but the sstate fetch code tries to fetch them leading
to confusing warnings and reduced debug capability.
This change ensures we touch any sig/siginfo files present and should
help ageing of the objects on sstate mirrors. It doesn't handle the intermediate
task siginfo files but those are never fetched by the current sstate code
so are an order of magnitude less problematic.
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
