kprobes: enable clean usage of get_kprobe

Allow clean use of get_kprobe() outside of core kprobe code. Ftrace makes use
of get_kprobe to identify probes installed on mcount call-sites.

Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: jkenisto@us.ibm.com
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 1036631..04a3556 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -259,6 +259,10 @@
 struct jprobe;
 struct kretprobe;
 
+static inline struct kprobe *get_kprobe(void *addr)
+{
+	return NULL;
+}
 static inline struct kprobe *kprobe_running(void)
 {
 	return NULL;