dmaengine: tegra-apb: remove unused tdma_read function

clang with W=1 reports
drivers/dma/tegra20-apb-dma.c:236:19: error: unused function
  'tdma_read' [-Werror,-Wunused-function]
static inline u32 tdma_read(struct tegra_dma *tdma, u32 reg)
                  ^
This function is not used so remove it.
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20230322121001.2569909-1-trix@redhat.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/tegra20-apb-dma.c

@@ -233,11 +233,6 @@ static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val)
 	writel(val, tdma->base_addr + reg);
 }
 
-static inline u32 tdma_read(struct tegra_dma *tdma, u32 reg)
-{
-	return readl(tdma->base_addr + reg);
-}
-
 static inline void tdc_write(struct tegra_dma_channel *tdc,
 			     u32 reg, u32 val)
 {