x86: unused variable in dma_alloc_coherent_gfp_flags()

Fixed a warning caused by a badly placed ifdef.

Signed-off-by: Steven Noonan <steven@uplinklabs.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/asm-x86/dma-mapping.h b/include/asm-x86/dma-mapping.h
index 0cc022b..5607532 100644
--- a/include/asm-x86/dma-mapping.h
+++ b/include/asm-x86/dma-mapping.h
@@ -253,9 +253,9 @@
 
 static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
 {
+#ifdef CONFIG_X86_64
 	unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp);
 
-#ifdef CONFIG_X86_64
 	if (dma_mask <= DMA_32BIT_MASK && !(gfp & GFP_DMA))
 		gfp |= GFP_DMA32;
 #endif