Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
diff --git a/include/linux/nfsd/nfsfh.h b/include/linux/nfsd/nfsfh.h
index 80d55bb..f76d80c 100644
--- a/include/linux/nfsd/nfsfh.h
+++ b/include/linux/nfsd/nfsfh.h
@@ -49,7 +49,7 @@
  *
  * The auth_type field specifies how the filehandle can be authenticated
  * This might allow a file to be confirmed to be in a writable part of a
- * filetree without checking the path from it upto the root.
+ * filetree without checking the path from it up to the root.
  * Current values:
  *     0  - No authentication.  fb_auth is 0 bytes long
  * Possible future values: