spi: stm32: remove SPI LOOP mode

This driver does not support SPI LOOP mode by configuration
in registers.

Signed-off-by: Cezary Gapinski <cezary.gapinski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-stm32.c

@@ -1143,7 +1143,7 @@ static int stm32_spi_probe(struct platform_device *pdev)
 	master->auto_runtime_pm = true;
 	master->bus_num = pdev->id;
 	master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LSB_FIRST |
-			    SPI_3WIRE | SPI_LOOP;
+			    SPI_3WIRE;
 	master->bits_per_word_mask = stm32_spi_get_bpw_mask(spi);
 	master->max_speed_hz = spi->clk_rate / SPI_MBR_DIV_MIN;
 	master->min_speed_hz = spi->clk_rate / SPI_MBR_DIV_MAX;