increase 5 ticks of ACK prepare interval (observed from debugging pin) as opentimer callback taking longer time than before.
#define PORT_maxTxDataPrepare 10 // 305us (measured 82us)
#define PORT_maxRxAckPrepare 10 // 305us (measured 83us)
#define PORT_maxRxDataPrepare 4 // 122us (measured 22us)
- #define PORT_maxTxAckPrepare 10 // 122us (measured 94us)
+ #define PORT_maxTxAckPrepare 15 // 122us (measured 94us)
// radio speed related
#ifdef L2_SECURITY_ACTIVE
#define PORT_delayTx 14 // 366us (measured xxxus)
