devtool: upgrade: fix handling of non-absolute paths
If your BBLAYERS has non-absolute paths in it (e.g.
"${COREBASE}/../something") then none of the paths matched in
copy_recipe_files() with the result that no files got copied and you
ended up with an error later on because the recipe file couldn't be
found at the destination. Fix this as well as adding an explicit check
to see if no files got copied - error out earlier if so.
Fixes [YOCTO #10981].
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
