Update to v4.19 kernel headers.

Test: Builds and boots.
Change-Id: I99a9ed79666e143b47f02ca4e59eed94f69b7e4a
(cherry picked from commit a981e2e52e2e95a65fa9c9b6fb16dcb4c83dd576)
diff --git a/libc/kernel/uapi/linux/if_xdp.h b/libc/kernel/uapi/linux/if_xdp.h
new file mode 100644
index 0000000..a0935bd
--- /dev/null
+++ b/libc/kernel/uapi/linux/if_xdp.h
@@ -0,0 +1,70 @@
+/****************************************************************************
+ ****************************************************************************
+ ***
+ ***   This header was automatically generated from a Linux kernel header
+ ***   of the same name, to make information necessary for userspace to
+ ***   call into the kernel available to libc.  It contains only constants,
+ ***   structures, and macros generated from the original header, and thus,
+ ***   contains no copyrightable information.
+ ***
+ ***   To edit the content of this header, modify the corresponding
+ ***   source file (e.g. under external/kernel-headers/original/) then
+ ***   run bionic/libc/kernel/tools/update_all.py
+ ***
+ ***   Any manual change here will be lost the next time this script will
+ ***   be run. You've been warned!
+ ***
+ ****************************************************************************
+ ****************************************************************************/
+#ifndef _LINUX_IF_XDP_H
+#define _LINUX_IF_XDP_H
+#include <linux/types.h>
+#define XDP_SHARED_UMEM (1 << 0)
+#define XDP_COPY (1 << 1)
+#define XDP_ZEROCOPY (1 << 2)
+struct sockaddr_xdp {
+  __u16 sxdp_family;
+  __u16 sxdp_flags;
+  __u32 sxdp_ifindex;
+  __u32 sxdp_queue_id;
+  __u32 sxdp_shared_umem_fd;
+};
+struct xdp_ring_offset {
+  __u64 producer;
+  __u64 consumer;
+  __u64 desc;
+};
+struct xdp_mmap_offsets {
+  struct xdp_ring_offset rx;
+  struct xdp_ring_offset tx;
+  struct xdp_ring_offset fr;
+  struct xdp_ring_offset cr;
+};
+#define XDP_MMAP_OFFSETS 1
+#define XDP_RX_RING 2
+#define XDP_TX_RING 3
+#define XDP_UMEM_REG 4
+#define XDP_UMEM_FILL_RING 5
+#define XDP_UMEM_COMPLETION_RING 6
+#define XDP_STATISTICS 7
+struct xdp_umem_reg {
+  __u64 addr;
+  __u64 len;
+  __u32 chunk_size;
+  __u32 headroom;
+};
+struct xdp_statistics {
+  __u64 rx_dropped;
+  __u64 rx_invalid_descs;
+  __u64 tx_invalid_descs;
+};
+#define XDP_PGOFF_RX_RING 0
+#define XDP_PGOFF_TX_RING 0x80000000
+#define XDP_UMEM_PGOFF_FILL_RING 0x100000000ULL
+#define XDP_UMEM_PGOFF_COMPLETION_RING 0x180000000ULL
+struct xdp_desc {
+  __u64 addr;
+  __u32 len;
+  __u32 options;
+};
+#endif