Fix missing sizeof().

Author: jfb8856606

lib/ff_syscall_wrapper.c

@@ -559,7 +559,7 @@ freebsd2linux_cmsghdr(struct linux_msghdr *linux_msg, const struct msghdr *freeb
                         *linux_optval = *freebsd_optval;
                         break;
                     case IP_RECVTTL:
-                        linux_cmsg->cmsg_len = LINUX_CMSG_LEN(int);
+                        linux_cmsg->cmsg_len = LINUX_CMSG_LEN(sizeof(int));
                         linux_cmsg->cmsg_type = LINUX_IP_TTL;
                         *(int *)linux_optval = *freebsd_optval;
                         break;