file_utils: move dup_cloexec() to header

src/lxc/file_utils.c

@@ -564,20 +564,6 @@ int fd_cloexec(int fd, bool cloexec)
 	return 0;
 }
 
-static inline int dup_cloexec(int fd)
-{
-	__do_close int fd_dup = -EBADF;
-
-	fd_dup = dup(fd);
-	if (fd_dup < 0)
-		return -errno;
-
-	if (fd_cloexec(fd_dup, true))
-		return -errno;
-
-	return move_fd(fd_dup);
-}
-
 FILE *fdopen_at(int dfd, const char *path, const char *mode,
 		unsigned int o_flags, unsigned int resolve_flags)
 {

src/lxc/file_utils.h

@@ -104,4 +104,18 @@ __hidden extern ssize_t lxc_read_try_buf_at(int dfd, const char *path,
  */
 __hidden extern bool same_file_lax(int fda, int fdb);
 
+static inline int dup_cloexec(int fd)
+{
+	__do_close int fd_dup = -EBADF;
+
+	fd_dup = dup(fd);
+	if (fd_dup < 0)
+		return -errno;
+
+	if (fd_cloexec(fd_dup, true))
+		return -errno;
+
+	return move_fd(fd_dup);
+}
+
 #endif /* __LXC_FILE_UTILS_H */