[glib] gmessages: Fix documentation formatting

[Philip Withnall <pwithnall src gnome org>]

commit e8487812b9782b6a01e8de9990593558394f4087
Author: Philip Withnall <withnall endlessm com>
Date:   Tue Apr 18 11:58:28 2017 +0100

    gmessages: Fix documentation formatting

 glib/gmessages.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/glib/gmessages.c b/glib/gmessages.c
index 130db65..eba1255 100644
--- a/glib/gmessages.c
+++ b/glib/gmessages.c
@@ -1651,8 +1651,8 @@ done_query:
  * ]|
  *
  * Note also that, even if no other structured fields are specified, there
- * must always be a "MESSAGE" key before the format string. The "MESSAGE"-format
- * pair has to be the last of the key-value pairs, and "MESSAGE" is the only
+ * must always be a `MESSAGE` key before the format string. The `MESSAGE`-format
+ * pair has to be the last of the key-value pairs, and `MESSAGE` is the only
  * field for which printf()-style formatting is supported.
  *
  * The default writer function for `stdout` and `stderr` will automatically