create-spdx: handle links to inaccessible locations

When a link is pointing to location inaccessible to build user (e.g. "/root/something"),
filepath.is_file() throws "PermissionError: [Errno 13] Permission denied".
Fix this by first checking if it is a link.

(From OE-Core rev: e105befbe4ee0d85e94c2048a744f0373e2dbcdf)

Signed-off-by: Peter Marko <peter.marko@siemens.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/create-spdx.bbclass

@@ -218,7 +218,7 @@ def add_package_files(d, doc, spdx_pkg, topdir, get_spdxid, get_types, *, archiv
             filepath = Path(subdir) / file
             filename = str(filepath.relative_to(topdir))
 
-            if filepath.is_file() and not filepath.is_symlink():
+            if not filepath.is_symlink() and filepath.is_file():
                 spdx_file = oe.spdx.SPDXFile()
                 spdx_file.SPDXID = get_spdxid(file_counter)
                 for t in get_types(filepath):