fix FAPPEND typo on x86_64 (previously only fixed on i386)

arch/x86_64/bits/fcntl.h

@@ -18,7 +18,7 @@
 #define F_DUPFD_CLOEXEC 1030
 
 #ifdef _GNU_SOURCE
-#define FAPPENT O_APPEND
+#define FAPPEND O_APPEND
 #define FFSYNC O_FSYNC
 #define FASYNC O_ASYNC
 #define FNONBLOCK O_NONBLOCK