[balsa] mailbox: Fix thinko

[Peter Bloomfield <peterb src gnome org>]

commit fce9bdf54d3aea7a54a5032b190d60d335266cfc
Author: Peter Bloomfield <PeterBloomfield bellsouth net>
Date:   Fri Jan 10 15:29:46 2020 -0500

    mailbox: Fix thinko

 libbalsa/mailbox.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/libbalsa/mailbox.c b/libbalsa/mailbox.c
index d595f7508..0ffacb80c 100644
--- a/libbalsa/mailbox.c
+++ b/libbalsa/mailbox.c
@@ -927,7 +927,7 @@ lbm_run_filters_on_reception_idle_cb(LibBalsaMailbox * mailbox)
                 /* mailbox could have been closed during set-fraction */
                 if (!LIBBALSA_IS_MAILBOX(mailbox))
                     is_open = is_mailbox = FALSE;
-                else if (!LIBBALSA_MAILBOX_OPEN(mailbox))
+                else if (!MAILBOX_OPEN(mailbox))
                     is_open = FALSE;
 
                 if (!is_open)