error-injection: Separate error-injection from kprobe

Since error-injection framework is not limited to be used
by kprobes, nor bpf. Other kernel subsystems can use it
freely for checking safeness of error-injection, e.g.
livepatch, ftrace etc.
So this separate error-injection framework from kprobes.

Some differences has been made:

- "kprobe" word is removed from any APIs/structures.
- BPF_ALLOW_ERROR_INJECTION() is renamed to
  ALLOW_ERROR_INJECTION() since it is not limited for BPF too.
- CONFIG_FUNCTION_ERROR_INJECTION is the config item of this
  feature. It is automatically enabled if the arch supports
  error injection feature for kprobe or ftrace etc.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

kernel/module.c

@@ -3118,10 +3118,10 @@ static int find_module_sections(struct module *mod, struct load_info *info)
 					     sizeof(*mod->ftrace_callsites),
 					     &mod->num_ftrace_callsites);
 #endif
-#ifdef CONFIG_BPF_KPROBE_OVERRIDE
-	mod->kprobe_ei_funcs = section_objs(info, "_kprobe_error_inject_list",
-					    sizeof(*mod->kprobe_ei_funcs),
-					    &mod->num_kprobe_ei_funcs);
+#ifdef CONFIG_FUNCTION_ERROR_INJECTION
+	mod->ei_funcs = section_objs(info, "_error_injection_whitelist",
+					    sizeof(*mod->ei_funcs),
+					    &mod->num_ei_funcs);
 #endif
 	mod->extable = section_objs(info, "__ex_table",
 				    sizeof(*mod->extable), &mod->num_exentries);