Change hardcoded literal '2902' to use const GATT_CLIENT_CHARAC_CFG_U…

…UID_S

lib/hci-socket/gatt.js

@@ -39,6 +39,7 @@ const GATT_INCLUDE_UUID               = 0x2802;
 const GATT_CHARAC_UUID                = 0x2803;
 
 const GATT_CLIENT_CHARAC_CFG_UUID     = 0x2902;
+const GATT_CLIENT_CHARAC_CFG_UUID_S   = '2902'
 const GATT_SERVER_CHARAC_CFG_UUID     = 0x2903;
 
 const ATT_ECODE_SUCCESS               = 0x00;
@@ -208,7 +209,7 @@ class Gatt  extends EventEmitter {
           this._handles[clientCharacteristicConfigurationDescriptorHandle] = {
             type: 'descriptor',
             handle: clientCharacteristicConfigurationDescriptorHandle,
-            uuid: '2902',
+            uuid: GATT_CLIENT_CHARAC_CFG_UUID_S,
             attribute: characteristic,
             properties: (0x02 | 0x04 | 0x08), // read/write
             secure: (secure & 0x10) ? (0x02 | 0x04 | 0x08) : 0,
@@ -223,7 +224,7 @@ class Gatt  extends EventEmitter {
           //above, if the characteristic defines notify, the 2902 characteristic descriptor is added automatically
           //if the peripheral also declares this, we don't want to add it again
           //flags (properties, secure etc) above are better defined
-          if(descriptor.uuid == '2902')
+          if(descriptor.uuid == GATT_CLIENT_CHARAC_CFG_UUID_S)
           {
             continue;
           }