[balsa: 1/2] Include fcntl.h for open()/fcntl()

[Peter Bloomfield <peterb src gnome org>]

commit 669aac6aede7bb0bdedfc81b9640c62ed2ea2d90
Author: Matt Turner <mattst88 gmail com>
Date:   Sat Apr 9 12:19:45 2022 -0700

    Include fcntl.h for open()/fcntl()
    
    Fails to build against musl libc otherwise.
    
    Bug: https://bugs.gentoo.org/831998

 libbalsa/misc.c | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/libbalsa/misc.c b/libbalsa/misc.c
index 3b529c6c9..241529d0d 100644
--- a/libbalsa/misc.c
+++ b/libbalsa/misc.c
@@ -30,6 +30,9 @@
 #define _SVID_SOURCE           1
 #include <ctype.h>
 #include <errno.h>
+#ifdef USE_FCNTL
+# include <fcntl.h>
+#endif
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>