ppc32: Add missing [pci_]dma_mapping_error()

diff -urN linux-2.5/include/asm-ppc/dma-mapping.h linuxppc-2.5-benh/include/asm-ppc/dma-mapping.h
@@ -184,4 +184,10 @@
 {
 	consistent_sync(vaddr, size, (int)direction);
 }
+
+static inline int dma_mapping_error(dma_addr_t dma_addr)
+{
+	return 0;
+}
+
 #endif				/* __ASM_PPC_DMA_MAPPING_H */

diff -urN linux-2.5/include/asm-ppc/pci.h linuxppc-2.5-benh/include/asm-ppc/pci.h
@@ -290,6 +290,11 @@
 	/* Nothing to do. */
 }
 
+static inline int pci_dma_mapping_error(dma_addr_t dma_addr)
+{
+	return 0;
+}
+
 /* Return the index of the PCI controller for device PDEV. */
 #define pci_domain_nr(bus) ((struct pci_controller *)(bus)->sysdata)->index