fix: bitmasking in smartConfigure to prevent overwrite of cfg0 #1489
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As mentioned in this issue microsoft/pxt-arcade#6438 changing the CFG0 bytes does not lead to the desired change in e.g. the offset values for the display when the display type is set to 4242 (Smart Display). I could trace this down to the smartConfigure function, in which in line 173 or 175 the content of the cfg0 variable is currently rewritten to either 0x80 or 0x40. Since the smartConfigure function is called before the offset values are read out (line 82), the rewriting leads to an erasure of the offset values. My proposed fix is to bitmask writing the cfg0 variable to keep all bytes despite the LSB.