Made modifications to account for:
- .siginfo files present in sstate-cache from non sstate-enabled tasks
- new naming format for sstate files
(From OE-Core rev: d23ad4255ad7465383286fa7805392aa70845ace)
Signed-off-by: Corneliu Stoicescu <corneliux.stoicescu@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>