ARM: OMAP: DMA: Fix compile for DMA chaining

FYI... without PATCH 1/1 the new DMA stuff doesn't compile on OMAP2.
While waiting for that fix, at least this is required to build in
current git
Signed-off-by: Tony Lindgren <tony@atomide.com>

include/asm-arm/arch-omap/dma.h

@@ -62,6 +62,7 @@
 #define OMAP_DMA4_IRQENABLE_L2		(OMAP_DMA4_BASE + 0x20)
 #define OMAP_DMA4_IRQENABLE_L3		(OMAP_DMA4_BASE + 0x24)
 #define OMAP_DMA4_SYSSTATUS		(OMAP_DMA4_BASE + 0x28)
+#define OMAP_DMA4_OCP_SYSCONFIG		(OMAP_DMA4_BASE + 0x2c)
 #define OMAP_DMA4_CAPS_0		(OMAP_DMA4_BASE + 0x64)
 #define OMAP_DMA4_CAPS_2		(OMAP_DMA4_BASE + 0x6c)
 #define OMAP_DMA4_CAPS_3		(OMAP_DMA4_BASE + 0x70)