Auto merge of #2740 - junhochoi:ip_dontfrag_freebsdlike, r=Amanieu

Add IP_DONTFRAG and IPV6_DONTFRAG for FreeBSD-like

FreeBSD: add IP_DONTFRAG
FreeBSD, DragonFlyBSD: add IPV6_DONTFRAG

Author: bors

libc-test/semver/dragonfly.txt

@@ -489,6 +489,7 @@ IPV6_PKTINFO
 IPV6_RECVPKTINFO
 IPV6_RECVTCLASS
 IPV6_TCLASS
+IPV6_DONTFRAG
 IP_HDRINCL
 IP_RECVDSTADDR
 IP_RECVIF

libc-test/semver/freebsd.txt

@@ -539,13 +539,15 @@ IPV6_RECVORIGDSTADDR
 IPV6_RECVPKTINFO
 IPV6_RECVTCLASS
 IPV6_TCLASS
+IPV6_DONTFRAG
 IP_BINDANY
 IP_BINDMULTI
 IP_HDRINCL
 IP_ORIGDSTADDR
 IP_RECVDSTADDR
 IP_RECVIF
 IP_RECVORIGDSTADDR
+IP_DONTFRAG
 IP_RECVTOS
 IP_RSS_LISTEN_BUCKET
 IP_SENDSRCADDR

src/unix/bsd/freebsdlike/freebsd/mod.rs

@@ -2886,6 +2886,7 @@ pub const IP_RSS_LISTEN_BUCKET: ::c_int = 26;
 pub const IP_ORIGDSTADDR: ::c_int = 27;
 pub const IP_RECVORIGDSTADDR: ::c_int = IP_ORIGDSTADDR;
 
+pub const IP_DONTFRAG: ::c_int = 67;
 pub const IP_RECVTOS: ::c_int = 68;
 
 pub const IPV6_BINDANY: ::c_int = 64;

src/unix/bsd/freebsdlike/mod.rs

@@ -963,6 +963,7 @@ pub const IPV6_PKTINFO: ::c_int = 46;
 pub const IPV6_HOPLIMIT: ::c_int = 47;
 pub const IPV6_RECVTCLASS: ::c_int = 57;
 pub const IPV6_TCLASS: ::c_int = 61;
+pub const IPV6_DONTFRAG: ::c_int = 62;
 
 pub const TCP_NOPUSH: ::c_int = 4;
 pub const TCP_NOOPT: ::c_int = 8;