Update to v4.17.3 kernel headers.

Test: Builds, boots on a walleye.
Change-Id: I389d8b61ec00ea309e38d1b1a2e0dace48c21edb
diff --git a/libc/kernel/uapi/rdma/ib_user_mad.h b/libc/kernel/uapi/rdma/ib_user_mad.h
index cd723bb..dadb590 100644
--- a/libc/kernel/uapi/rdma/ib_user_mad.h
+++ b/libc/kernel/uapi/rdma/ib_user_mad.h
@@ -61,7 +61,7 @@
 };
 struct ib_user_mad {
   struct ib_user_mad_hdr hdr;
-  __u64 data[0];
+  __aligned_u64 data[0];
 };
 typedef unsigned long __attribute__((aligned(4))) packed_ulong;
 #define IB_USER_MAD_LONGS_PER_METHOD_MASK (128 / (8 * sizeof(long)))
@@ -85,7 +85,7 @@
   __u8 mgmt_class_version;
   __u16 res;
   __u32 flags;
-  __u64 method_mask[2];
+  __aligned_u64 method_mask[2];
   __u32 oui;
   __u8 rmpp_version;
   __u8 reserved[3];