MINOR: actions: Export actions lookup functions

These functions will be useful to check if a keyword is already registered.
This will be needed by a next patch to fix a bug, and will need to be
backported.

(cherry picked from commit 7a71a6d9d262d7a0f7c3d208ab339d469958011d)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
diff --git a/src/http_rules.c b/src/http_rules.c
index 87d32f3..2ac1fef 100644
--- a/src/http_rules.c
+++ b/src/http_rules.c
@@ -51,7 +51,7 @@
 /*
  * Return the struct http_req_action_kw associated to a keyword.
  */
-static struct action_kw *action_http_req_custom(const char *kw)
+struct action_kw *action_http_req_custom(const char *kw)
 {
 	return action_lookup(&http_req_keywords.list, kw);
 }
@@ -59,7 +59,7 @@
 /*
  * Return the struct http_res_action_kw associated to a keyword.
  */
-static struct action_kw *action_http_res_custom(const char *kw)
+struct action_kw *action_http_res_custom(const char *kw)
 {
 	return action_lookup(&http_res_keywords.list, kw);
 }
@@ -67,7 +67,7 @@
 /*
  * Return the struct http_after_res_action_kw associated to a keyword.
  */
-static struct action_kw *action_http_after_res_custom(const char *kw)
+struct action_kw *action_http_after_res_custom(const char *kw)
 {
 	return action_lookup(&http_after_res_keywords.list, kw);
 }