Use IPV6_HDRINCL on Linux(#563)

Instead of IP_HDRINCL in Socket:: set_header_included_v6.

Author: kntyskw

src/socket.rs

@@ -1674,6 +1674,9 @@ impl Socket {
             setsockopt(
                 self.as_raw(),
                 sys::IPPROTO_IPV6,
+                #[cfg(target_os = "linux")]
+                sys::IPV6_HDRINCL,
+                #[cfg(not(target_os = "linux"))]
                 sys::IP_HDRINCL,
                 included as c_int,
             )

src/sys/unix.rs

@@ -124,6 +124,8 @@ pub(crate) use libc::SO_OOBINLINE;
 // Used in `Socket`.
 #[cfg(not(target_os = "nto"))]
 pub(crate) use libc::ipv6_mreq as Ipv6Mreq;
+#[cfg(all(feature = "all", target_os = "linux"))]
+pub(crate) use libc::IPV6_HDRINCL;
 #[cfg(all(
     feature = "all",
     not(any(