ftrace: Do not blindly read the ip address in ftrace_bug()
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v4.4.273 by commit 0bc62e398bbd9e600959e610def5109957437b28, it was introduced in version v2.6.28 by commit 05736a427f7e16be948ccbf39782bd3a6ae16b14. For more details please see the references link.