Update to v4.17.3 kernel headers.

Test: Builds, boots on a walleye.
Change-Id: I389d8b61ec00ea309e38d1b1a2e0dace48c21edb
diff --git a/libc/kernel/uapi/linux/dvb/dmx.h b/libc/kernel/uapi/linux/dvb/dmx.h
index d4ea26e..e142e57 100644
--- a/libc/kernel/uapi/linux/dvb/dmx.h
+++ b/libc/kernel/uapi/linux/dvb/dmx.h
@@ -85,6 +85,30 @@
   unsigned int base;
   __u64 stc;
 };
+enum dmx_buffer_flags {
+  DMX_BUFFER_FLAG_HAD_CRC32_DISCARD = 1 << 0,
+  DMX_BUFFER_FLAG_TEI = 1 << 1,
+  DMX_BUFFER_PKT_COUNTER_MISMATCH = 1 << 2,
+  DMX_BUFFER_FLAG_DISCONTINUITY_DETECTED = 1 << 3,
+  DMX_BUFFER_FLAG_DISCONTINUITY_INDICATOR = 1 << 4,
+};
+struct dmx_buffer {
+  __u32 index;
+  __u32 bytesused;
+  __u32 offset;
+  __u32 length;
+  __u32 flags;
+  __u32 count;
+};
+struct dmx_requestbuffers {
+  __u32 count;
+  __u32 size;
+};
+struct dmx_exportbuffer {
+  __u32 index;
+  __u32 flags;
+  __s32 fd;
+};
 #define DMX_START _IO('o', 41)
 #define DMX_STOP _IO('o', 42)
 #define DMX_SET_FILTER _IOW('o', 43, struct dmx_sct_filter_params)
@@ -98,4 +122,9 @@
 typedef enum dmx_input dmx_input_t;
 typedef enum dmx_ts_pes dmx_pes_type_t;
 typedef struct dmx_filter dmx_filter_t;
+#define DMX_REQBUFS _IOWR('o', 60, struct dmx_requestbuffers)
+#define DMX_QUERYBUF _IOWR('o', 61, struct dmx_buffer)
+#define DMX_EXPBUF _IOWR('o', 62, struct dmx_exportbuffer)
+#define DMX_QBUF _IOWR('o', 63, struct dmx_buffer)
+#define DMX_DQBUF _IOWR('o', 64, struct dmx_buffer)
 #endif