sparc64: fix sparse warning in pci.c

Fix following warning:
pci.c:886:5: warning: symbol 'pci64_dma_supported' was not declared. Should it be static?

Add proper prototype in kernel.h and delete local prototype in iommu.c

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/kernel/pci.c b/arch/sparc/kernel/pci.c
index 1555bbc..38fd867 100644
--- a/arch/sparc/kernel/pci.c
+++ b/arch/sparc/kernel/pci.c
@@ -28,6 +28,7 @@
 #include <asm/apb.h>
 
 #include "pci_impl.h"
+#include "kernel.h"
 
 /* List of all PCI controllers found in the system. */
 struct pci_pbm_info *pci_pbm_root = NULL;