signedMag12ToFloat issue for negative numbers

[espHorst]

I think that the last line of function

float Adafruit_AMG88xx::signedMag12ToFloat(uint16_t val)
{
	//take first 11 bits as absolute val
	uint16_t absVal = (val & 0x7FF);
	
	return (val & 0x8000) ? 0 - (float)absVal : (float)absVal ;
}

should read

	return (val & 0x800) ? 0 - (float)absVal : (float)absVal ;

according to the data sheet page 13 as the thermistor only returns 12 bit.

[deanm1278]

fixed!