ITE: drivers/i2c target mode: Fix racing condition

The finish interrupt after the previous transaction is completed may
occur in the next transaction. To do hardware reset at this time could
potentially lead to the failure of the transaction.
Therefore, removing the hardware reset upon completing the transaction
helps to avoid a race condition.

Signed-off-by: Tim Lin <tim2.lin@ite.corp-partner.google.com>
Signed-off-by: Dino Li <Dino.Li@ite.com.tw>