Add dma_debug_init() for ia64

The commit 9916219579d078c80377dd3988c2cc213536d868 was supposed to
add CONFIG_DMA_API_DEBUG support to IA64 however I forgot to add
dma_debug_init().

Signed-off-by: fujita <fujita@tulip.osrg.net>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>

arch/ia64/kernel/dma-mapping.c

@@ -6,6 +6,14 @@ int iommu_detected __read_mostly;
 struct dma_map_ops *dma_ops;
 EXPORT_SYMBOL(dma_ops);
 
+#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
+
+static int __init dma_init(void)
+{
+       dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
+}
+fs_initcall(dma_init);
+
 struct dma_map_ops *dma_get_ops(struct device *dev)
 {
 	return dma_ops;