Update to v4.17.3 kernel headers.

Test: Builds, boots on a walleye.
Change-Id: I389d8b61ec00ea309e38d1b1a2e0dace48c21edb
diff --git a/libc/kernel/uapi/linux/can/netlink.h b/libc/kernel/uapi/linux/can/netlink.h
index 7df626d..ddf9058 100644
--- a/libc/kernel/uapi/linux/can/netlink.h
+++ b/libc/kernel/uapi/linux/can/netlink.h
@@ -92,6 +92,7 @@
   IFLA_CAN_TERMINATION_CONST,
   IFLA_CAN_BITRATE_CONST,
   IFLA_CAN_DATA_BITRATE_CONST,
+  IFLA_CAN_BITRATE_MAX,
   __IFLA_CAN_MAX
 };
 #define IFLA_CAN_MAX (__IFLA_CAN_MAX - 1)