spi: dw: Replace incorrect spi_get_chipselect with set

Commit 445164e8 ("spi: dw: Replace spi->chip_select references with
function calls") replaced direct access to spi.chip_select with
spi_*_chipselect calls but incorrectly replaced a set instance with a
get instance, replace the incorrect instance.

Fixes: 445164e8

 ("spi: dw: Replace spi->chip_select references with function calls")
Signed-off-by: Abe Kohandel <abe.kohandel@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20230613162103.569812-1-abe.kohandel@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>