spi: ath79: remove spi-master setup and cleanup assignment

This removes the assignment of setup and cleanup functions for the ath79
target. Assigning the setup-method will lead to 'setup_transfer' not
being assigned in spi_bitbang_init. Because of this, performing any
TX/RX operation will lead to a kernel oops.

Also drop the redundant cleanup assignment, as it's also assigned in
spi_bitbang_init.
Signed-off-by: David Bauer <mail@david-bauer.net>
Link: https://lore.kernel.org/r/20210303160837.165771-2-mail@david-bauer.netSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-ath79.c

@@ -156,8 +156,6 @@ static int ath79_spi_probe(struct platform_device *pdev)
 
 	master->use_gpio_descriptors = true;
 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
-	master->setup = spi_bitbang_setup;
-	master->cleanup = spi_bitbang_cleanup;
 	master->flags = SPI_MASTER_GPIO_SS;
 	if (pdata) {
 		master->bus_num = pdata->bus_num;