Update to v4.17.3 kernel headers.

Test: Builds, boots on a walleye.
Change-Id: I389d8b61ec00ea309e38d1b1a2e0dace48c21edb
diff --git a/libc/kernel/uapi/linux/if_ether.h b/libc/kernel/uapi/linux/if_ether.h
index 04b6dae..4fb58f1 100644
--- a/libc/kernel/uapi/linux/if_ether.h
+++ b/libc/kernel/uapi/linux/if_ether.h
@@ -19,8 +19,8 @@
 #ifndef _UAPI_LINUX_IF_ETHER_H
 #define _UAPI_LINUX_IF_ETHER_H
 #include <linux/types.h>
-#include <linux/libc-compat.h>
 #define ETH_ALEN 6
+#define ETH_TLEN 2
 #define ETH_HLEN 14
 #define ETH_ZLEN 60
 #define ETH_DATA_LEN 1500
@@ -32,6 +32,7 @@
 #define ETH_P_PUP 0x0200
 #define ETH_P_PUPAT 0x0201
 #define ETH_P_TSN 0x22F0
+#define ETH_P_ERSPAN2 0x22EB
 #define ETH_P_IP 0x0800
 #define ETH_P_X25 0x0805
 #define ETH_P_ARP 0x0806
@@ -69,6 +70,7 @@
 #define ETH_P_AOE 0x88A2
 #define ETH_P_8021AD 0x88A8
 #define ETH_P_802_EX1 0x88B5
+#define ETH_P_PREAUTH 0x88C7
 #define ETH_P_TIPC 0x88CA
 #define ETH_P_MACSEC 0x88E5
 #define ETH_P_8021AH 0x88E7
@@ -117,6 +119,9 @@
 #define ETH_P_CAIF 0x00F7
 #define ETH_P_XDSA 0x00F8
 #define ETH_P_MAP 0x00F9
+#ifndef __UAPI_DEF_ETHHDR
+#define __UAPI_DEF_ETHHDR 1
+#endif
 #if __UAPI_DEF_ETHHDR
 struct ethhdr {
   unsigned char h_dest[ETH_ALEN];