[PATCH, libgo]: Fix syscall test failure on CentOS 5.11

[Uros Bizjak]

Hello!

syscall test fails on CentOS 5.11 with:

exec_linux_test.go:167:25: error: reference to undefined identifier
'syscall.CLONE_NEWNET'
   Unshareflags: syscall.CLONE_NEWNET,
                         ^
FAIL: syscall

Attached patch fixes the failure by providing CLONE_NEWNET definition.

Tested on x86_64-linux-gnu.

Uros.

diff --git a/libgo/mksysinfo.sh b/libgo/mksysinfo.sh
index 026bef2..ac5f086 100755
--- a/libgo/mksysinfo.sh
+++ b/libgo/mksysinfo.sh
@@ -1475,6 +1475,9 @@ grep '^const _CLONE_' gen-sysinfo.go | \
 if ! grep '^const CLONE_NEWUSER ' ${OUT} > /dev/null 2>&1; then
   echo "const CLONE_NEWUSER = 0x10000000" >> ${OUT}
 fi
+if ! grep '^const CLONE_NEWNET ' ${OUT} > /dev/null 2>&1; then
+  echo "const CLONE_NEWNET = 0x40000000" >> ${OUT}
+fi
 
 # Struct sizes.
 set cmsghdr Cmsghdr ip_mreq IPMreq ip_mreqn IPMreqn ipv6_mreq IPv6Mreq \