lib/oe/recipeutils: ignore archives by default in get_recipe_local_files()

lib/oe/recipeutils: ignore archives by default in get_recipe_local_files()

By default, have get_recipe_local_files() not return any archive
files. This prevents a local tarball from being erroneously removed
from SRC_URI if you run "devtool modify" on a recipe followed by
"devtool update-recipe". It doesn't actually help you to directly
update the contents of such tarballs, but at least now it won't break
the recipe.

(From OE-Core rev: e9c418d4704c1bed4c5880e176e5288485f4f5a6)

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>