sh: Fix up MAX_DMA_CHANNELS definition when DMA is disabled.

MAX_DMA_CHANNELS is tested for the total number of channels in order to
populate an IRQ map. Stub this out completely when no DMA support is
enabled -- as used to be the default behaviour before this was
generalized for use by the dmaengine code.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/include/asm/dma.h

@@ -20,8 +20,10 @@
 
 #ifdef CONFIG_NR_DMA_CHANNELS
 #  define MAX_DMA_CHANNELS	(CONFIG_NR_DMA_CHANNELS)
-#else
+#elif defined(CONFIG_NR_ONCHIP_DMA_CHANNELS)
 #  define MAX_DMA_CHANNELS	(CONFIG_NR_ONCHIP_DMA_CHANNELS)
+#else
+#  define MAX_DMA_CHANNELS	0
 #endif
 
 /*