ASoC: ux500: ux500_msp_i2s: Remove unused variables 'reg_val_DR' and 'reg_val_TSTDR'

ASoC: ux500: ux500_msp_i2s: Remove unused variables 'reg_val_DR' and 'reg_val_TSTDR'

Looks like these have been unchecked since the driver's inception in 2012.

Fixes the following W=1 kernel build warning(s):

sound/soc/ux500/ux500_msp_i2s.c: In function ‘flush_fifo_rx’:
sound/soc/ux500/ux500_msp_i2s.c:398:6: warning: variable ‘reg_val_DR’
set but not used [-Wunused-but-set-variable]
sound/soc/ux500/ux500_msp_i2s.c: In function ‘flush_fifo_tx’:
sound/soc/ux500/ux500_msp_i2s.c:415:6: warning: variable
‘reg_val_TSTDR’ set but not used [-Wunused-but-set-variable]

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Cc: zhong jiang <zhongjiang@huawei.com>
Cc: Ola Lilja <ola.o.lilja@stericsson.com>
Cc: Roger Nilsson <roger.xr.nilsson@stericsson.com>
Cc: Sandeep Kaushik <sandeep.kaushik@st.com>
Link: https://lore.kernel.org/r/20200709162328.259586-7-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>