This will help in running ptests like core layer, right now there are
just 3 but I hope to get more contributions now that infra is in place

to run all ptests

bitbake meta-filesystems-image-ptest-all

to run a single recipe ptests

bitbake meta-filesystems-image-ptest-fuse3

Signed-off-by: Khem Raj <raj.khem@gmail.com>