MT6835 wrong PPR

[pelukkk]

According to the MT6835 datasheet, the contents of the register ABZ_RES = PPR - 1, as 0x0000 = 1PPR.

MT6835::getABZResolution() and MT6835::setABZResolution() don't seem to take that into account. If this is the expected behaviour, and the user should know that they are setting the register content instead of the PPR, it should be mentioned in the readme and maybe a comment.

[runger1101001]

A fair point. I think I'll keep the current behaviour so as not to break existing code, but will document this more clearly. Thank you for reporting it.