Filter files from sound kits that has no paths

Unsure what's triggering this - for some reason we fail to find a path
for file 2144118 which has a path in the listfile, but it isn't picked
up.

Logically however code can't cope with path being null, so remove the
possibility and move on with life.

Exporter/SQL/Setup.sql

@@ -322,7 +322,7 @@ INNER JOIN
 LEFT OUTER JOIN
     File ON File.Id = SoundKitEntry.FileId
 WHERE
-    File.Path IS NULL OR (File.Path LIKE "sound/%" AND NOT IsMusicFileExcluded(File.Id, File.Path, File.ContentHash))
+    File.Path LIKE "sound/%" AND NOT IsMusicFileExcluded(File.Id, File.Path, File.ContentHash)
 ORDER BY
     SoundKitEntry.FileId;