ftrace/x86: Have x86 ftrace use the ftrace_modify_all_code()

To remove duplicate code, have the ftrace arch_ftrace_update_code()
use the generic ftrace_modify_all_code(). This requires that the
default ftrace_replace_code() becomes a weak function so that an
arch may override it.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 3c345825cc..a008663 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1683,7 +1683,7 @@
 	return -1; /* unknow ftrace bug */
 }
 
-static void ftrace_replace_code(int update)
+void __weak ftrace_replace_code(int enable)
 {
 	struct dyn_ftrace *rec;
 	struct ftrace_page *pg;
@@ -1693,7 +1693,7 @@
 		return;
 
 	do_for_each_ftrace_rec(pg, rec) {
-		failed = __ftrace_replace_code(rec, update);
+		failed = __ftrace_replace_code(rec, enable);
 		if (failed) {
 			ftrace_bug(failed, rec->ip);
 			/* Stop processing */