dmaengine: dw-edma: Drop unused dchan2dev() and chan2dev()

Static functions dchan2dev() and chan2dev() are not used, W=1 build:

dw-edma-core.c:27:16: error: unused function 'dchan2dev' [-Werror,-Wunused-function]
dw-edma-core.c:33:16: error: unused function 'chan2dev' [-Werror,-Wunused-function]

Fixes: e63d79d1ffcd ("dmaengine: Add Synopsys eDMA IP core driver")
Signed-off-by: Krzysztof Kozlowski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/dw-edma/dw-edma-core.c

···
 #include "../virt-dma.h"
 
 static inline
-struct device *dchan2dev(struct dma_chan *dchan)
-{
-	return &dchan->dev->device;
-}
-
-static inline
-struct device *chan2dev(struct dw_edma_chan *chan)
-{
-	return &chan->vc.chan.dev->device;
-}
-
-static inline
 struct dw_edma_desc *vd2dw_edma_desc(struct virt_dma_desc *vd)
 {
 	return container_of(vd, struct dw_edma_desc, vd);