Wire library read() returns 0xFF on reading only one byte

I am having a weird problem with my I2C code. The problem is that when I try to read only 1 byte in the master I get 0xFF but if I read 2 bytes I get proper value of the first byte.

```cpp
Wire.requestFrom(SLAVE_ADDRESS, 1);
data = Wire.read();
```

=> gives `data` as `0xFF`

```cpp
Wire.requestFrom(SLAVE_ADDRESS, 2);
data0 = Wire.read();
data1 = Wire.read();
```

=> gives `data0` as `0xA5` (which is expected from the single byte read)

Am I doing anything wrong?

The issue names the Wire.requestFrom() and Wire.read() entry points but no source file or test. Reproduce the one-byte and two-byte reads first, then trace those calls through the AVR Wire implementation. Done means the differing behavior is explained and the appropriate fix or documented usage is confirmed.

Written by the indexing model from the issue text.