cve-update-nvd2-native: Tweak to work better with NFS DL_DIR

After much debugging, the corruption issues on the autobuilder appear to
be due to the way sqlite accesses database files. It doesn't change the
file timestamp after making changes, which for reasons unknown, confuses
NFS. As soon as the file is touched, NFS becomes fine again accross the
whole cluster, as if by magic.

We could try and debug further but putting a "touch" call into the code
is easy and harmless. Lets hope this removes this annoying source of
errors.

(From OE-Core rev: f642edb006a8c16dbe45681afe547eabfae17073)

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

meta/recipes-core/meta/cve-update-nvd2-native.bb

@@ -90,6 +90,8 @@ python do_fetch() {
     if update_db_file(db_tmp_file, d, database_time) == True:
         # Update downloaded correctly, can swap files
         shutil.move(db_tmp_file, db_file)
+        # Need to 'touch' the file to ensure NFS sees the data
+        os.utime(db_file)
     else:
         # Update failed, do not modify the database
         bb.warn("CVE database update failed")