MINOR: hlua: declare hlua_gethlua() function

Declaring hlua_gethlua() function to make it usable from hlua_fcn.c.

include/haproxy/hlua.h

@@ -59,6 +59,7 @@ const char *hlua_show_current_location(const char *pfx);
 int hlua_ref(lua_State *L);
 void hlua_pushref(lua_State *L, int ref);
 void hlua_unref(lua_State *L, int ref);
+struct hlua *hlua_gethlua(lua_State *L);
 
 #else /* USE_LUA */
 

src/hlua.c

@@ -1294,7 +1294,7 @@ __LJMP int hlua_lua2arg_check(lua_State *L, int first, struct arg *argp,
  *  - hlua_gethlua : return the hlua context associated with an lua_State.
  *  - hlua_sethlua : create the association between hlua context and lua_state.
  */
-static inline struct hlua *hlua_gethlua(lua_State *L)
+inline struct hlua *hlua_gethlua(lua_State *L)
 {
 	struct hlua **hlua = lua_getextraspace(L);
 	return *hlua;