Read pipeline issues STOP despite SMB_TRANS_NOSTOP — chained I2C reads of >=2 bytes are terminated early

Summary

The rcount==2 pipeline allowance sets IG4_DATA_STOP without testing NOSTOP (the initial allowance and the write path both test it - intent proven): chained reads >=2 bytes get a premature STOP, follow-up chained transactions start with an unexpected fresh START, multi-part reads desync. Honor-NOSTOP fix.