spi_slave_hal_set_trans_bitlen() function

Context of the HAL layer.

Init the peripheral and the context.

Setup device-related configurations according to the settings in the context.

Rest peripheral registers to default value

Rest hw fifo in peripheral, for a CPU controlled trans

Push data needed to be transmit into hw fifo

Enable/Disable miso/mosi signals in peripheral

Trigger start a user-defined transaction.

Check whether the transaction is done (trans_done is set).

Post transaction operations, fetch data from the buffer and recorded the length.

Get the length of last transaction, in bits. Should be called after ``spi_slave_hal_store_result``. Note that if last transaction is longer than configured before, the return value still the actual length.

Check whether we need to reset the DMA according to the status of last transactions. In ESP32, sometimes we may need to reset the DMA for the slave before the next transaction. Call this to check it.

Deinit the peripheral (and the context if needed).