fix issue with central_uart sketch

Author: hathach

libraries/Bluefruit52Lib/examples/Central/central_bleuart/central_bleuart.ino

@@ -29,7 +29,7 @@ void setup()
   Serial.println("-----------------------------------\n");
 
   // Enable both peripheral and central
-  Bluefruit.begin(true, true);
+  Bluefruit.begin(0, 1);
   Bluefruit.setName("Bluefruit52 Central");
 
   // Configure DIS client

libraries/Bluefruit52Lib/src/BLECentral.cpp

@@ -83,7 +83,7 @@ bool BLECentral::connect(const ble_gap_addr_t* peer_addr)
 #if SD_VER < 500
   VERIFY_STATUS( sd_ble_gap_connect(peer_addr, Bluefruit.Scanner.getParams(), &gap_conn_params), false );
 #else
-  VERIFY_STATUS( sd_ble_gap_connect(peer_addr, Bluefruit.Scanner.getParams(), &gap_conn_params, BLE_CONN_CFG_TAG_DEFAULT), false );
+  VERIFY_STATUS( sd_ble_gap_connect(peer_addr, Bluefruit.Scanner.getParams(), &gap_conn_params, BLE_CONN_CFG_HIGH_BANDWIDTH), false );
 #endif
   return true;
 }