unix: add S_IRWXG and S_IRWXO to FreeBSD types

I found this during https://github.com/DataDog/datadog-agent/pull/2079

Change-Id: I51d57e7e3cedb8b23e720bc03f38504dc0ad063d
GitHub-Last-Rev: 4e1c193db8bfc9174f630903bfc26e5532555309
GitHub-Pull-Request: golang/sys#13
Reviewed-on: https://go-review.googlesource.com/126620
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/unix/types_freebsd.go b/unix/types_freebsd.go
index 4eb02cd..f4b6bf9 100644
--- a/unix/types_freebsd.go
+++ b/unix/types_freebsd.go
@@ -204,6 +204,8 @@
 	S_IRUSR  = C.S_IRUSR
 	S_IWUSR  = C.S_IWUSR
 	S_IXUSR  = C.S_IXUSR
+	S_IRWXG  = C.S_IRWXG
+	S_IRWXO  = C.S_IRWXO
 )
 
 type Stat_t C.struct_stat8
diff --git a/unix/ztypes_freebsd_386.go b/unix/ztypes_freebsd_386.go
index 878a21a..81793a2 100644
--- a/unix/ztypes_freebsd_386.go
+++ b/unix/ztypes_freebsd_386.go
@@ -71,6 +71,8 @@
 	S_IRUSR  = 0x100
 	S_IWUSR  = 0x80
 	S_IXUSR  = 0x40
+	S_IRWXG  = 0x38
+	S_IRWXO  = 0x7
 )
 
 type Stat_t struct {
diff --git a/unix/ztypes_freebsd_amd64.go b/unix/ztypes_freebsd_amd64.go
index 8408af1..6c7589b 100644
--- a/unix/ztypes_freebsd_amd64.go
+++ b/unix/ztypes_freebsd_amd64.go
@@ -71,6 +71,8 @@
 	S_IRUSR  = 0x100
 	S_IWUSR  = 0x80
 	S_IXUSR  = 0x40
+	S_IRWXG  = 0x38
+	S_IRWXO  = 0x7
 )
 
 type Stat_t struct {
diff --git a/unix/ztypes_freebsd_arm.go b/unix/ztypes_freebsd_arm.go
index 4b2d9a4..f620a12 100644
--- a/unix/ztypes_freebsd_arm.go
+++ b/unix/ztypes_freebsd_arm.go
@@ -73,6 +73,8 @@
 	S_IRUSR  = 0x100
 	S_IWUSR  = 0x80
 	S_IXUSR  = 0x40
+	S_IRWXG  = 0x38
+	S_IRWXO  = 0x7
 )
 
 type Stat_t struct {