kprobes: introduce weak arch_check_ftrace_location() helper function

kprobes: introduce weak arch_check_ftrace_location() helper function

Introduce weak arch_check_ftrace_location() helper function which
architectures can override in order to implement handling of kprobes
on function tracer call sites on their own, without depending on
common code or implementing the KPROBES_ON_FTRACE feature.

Signed-off-by: Heiko Carstens <[email protected]>
Acked-by: Masami Hiramatsu <[email protected]>
Acked-by: Steven Rostedt <[email protected]>
Signed-off-by: Martin Schwidefsky <[email protected]>