wifi: eswifi: init net_pkt cursor after net_pkt_write

Initialize the net_pkt cursor to begining after net_pkt_write.
Without which recv_cb can't peek/get net_pkt

Signed-off-by: Parthiban Nallathambi <parthitce@gmail.com>
diff --git a/drivers/wifi/eswifi/eswifi_offload.c b/drivers/wifi/eswifi/eswifi_offload.c
index dd92adf..55a20f6 100644
--- a/drivers/wifi/eswifi/eswifi_offload.c
+++ b/drivers/wifi/eswifi/eswifi_offload.c
@@ -97,6 +97,7 @@
 		LOG_WRN("Incomplete buffer copy");
 	}
 
+	net_pkt_cursor_init(pkt);
 	socket->recv_cb(socket->context, pkt,
 			NULL, NULL, 0, socket->user_data);
 	k_sem_give(&socket->read_sem);