sstate: Make do_recipe_qa and do_populate_lic non-arch specific

The sstate functions currently pull in STAMP and SSTATE_PKG which
end up pulling in DEFAULTTUNE and other variables. The location on
disk encodes all the "architecture" information we need so clean up
the dependencies of these tasks and make them non-architecture specific.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>