Fix broken reset logic if reset pin exceeds 127 due to int8 overflow

[nocnokneo]

When initializing a display like:

display.begin(0, true);

And with a rst_pin number greater than 127 (like 0xC2 in my case) fails because the number overflows the largest int8_t number and wraps around to negative value which is interpreted as "not connected".

This is in conjunction with adafruit/Adafruit-GFX-Library#449

[nocnokneo]

@ladyada @evaherrada Aside from fixing the CI check, any other changes you'd like to see to get this merged?

[ladyada]

hihi yes please fix the CI but also please use int32_t so we can still pass in -1
int16_t would also be plennnnty

[nocnokneo]

hihi yes please fix the CI but also please use int32_t so we can still pass in -1 int16_t would also be plennnnty

Done! Went with int16_t

[ladyada]

thank you :)

[nocnokneo]

Thanks! Don't forget the corresponding PR: adafruit/Adafruit-GFX-Library#449