BUG: config: error in http-response replace-header number of arguments

A couple of typo fixed in 'http-response replace-header':
- an error when counting the number of arguments
- a typo in the alert message

This should be backported to 1.5.
diff --git a/src/proto_http.c b/src/proto_http.c
index e679701..b792c6c 100644
--- a/src/proto_http.c
+++ b/src/proto_http.c
@@ -9361,8 +9361,8 @@
 		cur_arg = 1;
 
 		if (!*args[cur_arg] || !*args[cur_arg+1] || !*args[cur_arg+2] ||
-		    (*args[cur_arg+3] && strcmp(args[cur_arg+2], "if") != 0 && strcmp(args[cur_arg+2], "unless") != 0)) {
-			Alert("parsing [%s:%d]: 'http-request %s' expects exactly 3 arguments.\n",
+		    (*args[cur_arg+3] && strcmp(args[cur_arg+3], "if") != 0 && strcmp(args[cur_arg+3], "unless") != 0)) {
+			Alert("parsing [%s:%d]: 'http-response %s' expects exactly 3 arguments.\n",
 			      file, linenum, args[0]);
 			goto out_err;
 		}