dmaengine: shdma: Update SH_DMAC_MAX_CHANNELS to 20

Update SH_DMAC_MAX_CHANNELS to support the 20 DMA
channels included in the sh73a0 SY-DMAC hardware.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

drivers/dma/shdma.h

@@ -17,7 +17,7 @@
 #include <linux/interrupt.h>
 #include <linux/list.h>
 
-#define SH_DMAC_MAX_CHANNELS 6
+#define SH_DMAC_MAX_CHANNELS 20
 #define SH_DMA_SLAVE_NUMBER 256
 #define SH_DMA_TCR_MAX 0x00FFFFFF	/* 16MB */