[PATCH] Typo in error message in recvattach.c

[Richard Russon]

Typo picked up by Debian's QA.
This was allegedly fixed 5 years ago (#3493).

---

diff -urN mutt/recvattach.c mutt.fix/recvattach.c
--- mutt/recvattach.c   2016-03-17 23:22:15.549234200 +0000
+++ mutt.fix/recvattach.c       2016-03-17 23:13:25.254091758 +0000
@@ -707,7 +707,7 @@
        {
          if (!mutt_can_decode (top))
          {
-           mutt_error (_("I dont know how to print %s attachments!"), type);
+           mutt_error (_("I don't know how to print %s attachments!"), type);
            return (0);
          }
        }