x86/iommu: make GART driver checkpatch clean

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/asm-x86/gart.h b/include/asm-x86/gart.h
index 3f62a83..cdf4f78 100644
--- a/include/asm-x86/gart.h
+++ b/include/asm-x86/gart.h
@@ -29,6 +29,8 @@
 #define AMD64_GARTCACHECTL	0x9c
 #define AMD64_GARTEN		(1<<0)
 
+extern int agp_amd64_init(void);
+
 static inline void enable_gart_translation(struct pci_dev *dev, u64 addr)
 {
 	u32 tmp, ctl;