[tepl] EncodingConverter: add a FIXME comment about errno

[Sébastien Wilmet <swilmet src gnome org>]

commit 1386f8cfb2ec1a6c1d2eedf8603784a1e9aacf7e
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Wed May 29 11:08:03 2019 +0200

    EncodingConverter: add a FIXME comment about errno
    
    After reading the book "The UNIX programming environment" by
    Kernighan/Pike.

 tepl/tepl-encoding-converter.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/tepl/tepl-encoding-converter.c b/tepl/tepl-encoding-converter.c
index ad5963a..6c23ba5 100644
--- a/tepl/tepl-encoding-converter.c
+++ b/tepl/tepl-encoding-converter.c
@@ -39,6 +39,8 @@
  *   callback is called.
  */
 
+/* FIXME: I think errno should be reset to 0 after an errno error. */
+
 struct _TeplEncodingConverterPrivate
 {
        GIConv conv;