spi: dw: Remove unused variable in CR0 configuring hooks

spi: dw: Remove unused variable in CR0 configuring hooks

After enabling new IP support in the driver couple of variables
were left unused compiler is not happy about:

.../spi-dw.c: In function ‘dw_spi_update_cr0’:
.../spi-dw.c:264:17: warning: unused variable ‘dws’ [-Wunused-variable]
  264 |  struct dw_spi *dws = spi_controller_get_devdata(master);
      |                 ^~~
.../spi-dw.c: In function ‘dw_spi_update_cr0_v1_01a’:
.../spi-dw.c:285:17: warning: unused variable ‘dws’ [-Wunused-variable]
  285 |  struct dw_spi *dws = spi_controller_get_devdata(master);
      |                 ^~~

Drop them for good.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200506153025.21441-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>