Klocwork issues in CurieEEPROM

Klocwork found 2 issues in CurieEEPROM:
- CurieEEPROM.cpp (line 69): 
  Array 'blockdata' of size 128 may use index value(s) 128..511

```
int blockIndex = address/4;
blockdata[blockIndex] = data;
```

Same issue on:
- CurieEEPROM.cpp (line 127):
- CurieEEPROM.cpp (line 132):
