ASoC: amd: renoir: acp3x-pdm-dma: remove unnecessary assignments

cppcheck warning:

sound/soc/amd/renoir/acp3x-pdm-dma.c:132:17: style: Variable
'pdm_dma_enable' is assigned a value that is never
used. [unreadVariable]
 pdm_dma_enable = 0x00;
                ^
sound/soc/amd/renoir/acp3x-pdm-dma.c:156:18: style: Variable
'pdm_dma_enable' is assigned a value that is never
used. [unreadVariable]
  pdm_dma_enable = 0x00;
                 ^

indeed those values are never used because the timeout is reset.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20210326215927.936377-2-pierre-louis.bossart@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/amd/renoir/acp3x-pdm-dma.c

@@ -129,7 +129,6 @@ static int start_pdm_dma(void __iomem *acp_base)
 	enable_pdm_clock(acp_base);
 	rn_writel(pdm_enable, acp_base + ACP_WOV_PDM_ENABLE);
 	rn_writel(pdm_dma_enable, acp_base + ACP_WOV_PDM_DMA_ENABLE);
-	pdm_dma_enable = 0x00;
 	timeout = 0;
 	while (++timeout < ACP_COUNTER) {
 		pdm_dma_enable = rn_readl(acp_base + ACP_WOV_PDM_DMA_ENABLE);
@@ -153,7 +152,6 @@ static int stop_pdm_dma(void __iomem *acp_base)
 	if (pdm_dma_enable & 0x01) {
 		pdm_dma_enable = 0x02;
 		rn_writel(pdm_dma_enable, acp_base + ACP_WOV_PDM_DMA_ENABLE);
-		pdm_dma_enable = 0x00;
 		timeout = 0;
 		while (++timeout < ACP_COUNTER) {
 			pdm_dma_enable = rn_readl(acp_base +