fix off-by-one error in firmware_version indexes
fix off-by-one error in firmware_version indexes

dvorka/ttwatch,lgrangeia/ttwatch,dvorka/ttwatch,dvorka/ttwatch,ryanbinns/ttwatch,ryanbinns/ttwatch,lgrangeia/ttwatch,lgrangeia/ttwatch,dlenski/ttwatch,ryanbinns/ttwatch,lgrangeia/ttwatch,ryanbinns/ttwatch,dvorka/ttwatch,dlenski/ttwatch,dlenski/ttwatch,dlenski/ttwatch