bitbake: fetch2/npm: fix handling of os field

When I originally added this check I didn't quite understand how the
values in this field should be expressed - it seems from reading the
documentation if there is an entry starting with '!' then the list is
a blacklist and we shouldn't expect "linux" to be in the list, or we'll
end up skipping important dependencies.

This fixes fetching the "statsd" npm package.

Fixes [YOCTO #10760].

(Bitbake rev: 7aa6d1586417e0e7d9925917a82caee5884957db)

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

bitbake/lib/bb/fetch2/npm.py

@@ -182,7 +182,12 @@ class Npm(FetchMethod):
             if pkg_os:
                 if not isinstance(pkg_os, list):
                     pkg_os = [pkg_os]
-                if 'linux' not in pkg_os or '!linux' in pkg_os:
+                blacklist = False
+                for item in pkg_os:
+                    if item.startswith('!'):
+                        blacklist = True
+                        break
+                if (not blacklist and 'linux' not in pkg_os) or '!linux' in pkg_os:
                     logger.debug(2, "Skipping %s since it's incompatible with Linux" % pkg)
                     return
         #logger.debug(2, "Output URL is %s - %s - %s" % (ud.basepath, ud.basename, ud.localfile))