Update to v5.16 kernel headers.

Kernel headers coming from:

Git: https://android.googlesource.com/kernel/common/
Branch: android-mainline
Tag: android-mainline-5.16

Test: Builds and bionic unit tests pass.
Change-Id: I2522c4f2a0efb9f8a193e1f2d65868e478217502
diff --git a/libc/kernel/uapi/linux/if_ether.h b/libc/kernel/uapi/linux/if_ether.h
index 2890b36..1f7f8f2 100644
--- a/libc/kernel/uapi/linux/if_ether.h
+++ b/libc/kernel/uapi/linux/if_ether.h
@@ -67,6 +67,7 @@
 #define ETH_P_LINK_CTL 0x886c
 #define ETH_P_ATMFATE 0x8884
 #define ETH_P_PAE 0x888E
+#define ETH_P_REALTEK 0x8899
 #define ETH_P_AOE 0x88A2
 #define ETH_P_8021AD 0x88A8
 #define ETH_P_802_EX1 0x88B5