<rdar://problem/12243932> 
Change RNBSocket from using lockdown's lockdown_secure_checkin()
function to using lockdown's secure_lockdown_checkin() function.


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@172775 91177308-0d34-0410-b5e6-96231b3b80d8