caif: Use UTILITY_NAME_LENGTH instead of hard-coding 16

UTILITY_NAME_LENGTH is 16. So better use the former when defining the
'utility_name' array. This makes the intent clearer when it is used around
line 260.

While at it, declare variable in reverse xmas tree style.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/8c1160501f69b64bb2d45ce9f26f746eec80ac77.1711787352.git.christophe.jaillet@wanadoo.frSigned-off-by: Jakub Kicinski <kuba@kernel.org>

net/caif/cfctrl.c

@@ -201,14 +201,14 @@ int cfctrl_linkup_request(struct cflayer *layer,
 			  struct cflayer *user_layer)
 {
 	struct cfctrl *cfctrl = container_obj(layer);
+	struct cflayer *dn = cfctrl->serv.layer.dn;
+	char utility_name[UTILITY_NAME_LENGTH];
+	struct cfctrl_request_info *req;
+	struct cfpkt *pkt;
 	u32 tmp32;
 	u16 tmp16;
 	u8 tmp8;
-	struct cfctrl_request_info *req;
 	int ret;
-	char utility_name[16];
-	struct cfpkt *pkt;
-	struct cflayer *dn = cfctrl->serv.layer.dn;
 
 	if (!dn) {
 		pr_debug("not able to send linkup request\n");