alpha: remove unused DEBUG_FORCEDAC define in IOMMU

This just removes unused DEBUG_FORCEDAC define in the IOMMU code.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arch/alpha/kernel/pci_iommu.c

@@ -31,7 +31,6 @@
 #endif
 
 #define DEBUG_NODIRECT 0
-#define DEBUG_FORCEDAC 0
 
 #define ISA_DMA_MASK		0x00ffffff