Update to v5.8 kernel headers.

Kernel headers coming from:

Git: https://android.googlesource.com/kernel/common/
Branch: android-mainline
Tag: android-mainline-5.8

Test: NA
Change-Id: I2231c877589820fc09800a200cf4ac62ba74b04c
diff --git a/libc/kernel/uapi/linux/if_ether.h b/libc/kernel/uapi/linux/if_ether.h
index dd2dedb..c3e0718 100644
--- a/libc/kernel/uapi/linux/if_ether.h
+++ b/libc/kernel/uapi/linux/if_ether.h
@@ -73,6 +73,7 @@
 #define ETH_P_PREAUTH 0x88C7
 #define ETH_P_TIPC 0x88CA
 #define ETH_P_LLDP 0x88CC
+#define ETH_P_MRP 0x88E3
 #define ETH_P_MACSEC 0x88E5
 #define ETH_P_8021AH 0x88E7
 #define ETH_P_MVRP 0x88F5