wpa_supplicant: Increase UDP control interface RX buffer

Seems like some test cases, e.g., ap_wpa2_psk_ext_retry_msg_3c, require
larger buffer than 256 bytes.

In other case I fail such test cases when run on real HW and using:
CONFIG_CTRL_IFACE=udp-remote

Increase the RX buffer from 256 to 4096 bytes to match the other control
interface cases.

Signed-off-by: Janusz Dziedzic <janusz.dziedzic@gmail.com>

wpa_supplicant/ctrl_iface_udp.c

@@ -219,7 +219,7 @@ static void wpa_supplicant_ctrl_iface_receive(int sock, void *eloop_ctx,
 {
 	struct wpa_supplicant *wpa_s = eloop_ctx;
 	struct ctrl_iface_priv *priv = sock_ctx;
-	char buf[256], *pos;
+	char buf[4096], *pos;
 	int res;
 #ifdef CONFIG_CTRL_IFACE_UDP_IPV6
 	struct sockaddr_in6 from;
@@ -600,7 +600,7 @@ static void wpa_supplicant_global_ctrl_iface_receive(int sock, void *eloop_ctx,
 {
 	struct wpa_global *global = eloop_ctx;
 	struct ctrl_iface_global_priv *priv = sock_ctx;
-	char buf[256], *pos;
+	char buf[4096], *pos;
 	int res;
 #ifdef CONFIG_CTRL_IFACE_UDP_IPV6
 	struct sockaddr_in6 from;