MIPS/EDAC: Improve OCTEON EDAC support.

Some initialization errors are reported with the existing OCTEON EDAC
support patch.  Also some parts have more than one memory controller.

Fix the errors and add multiple controllers if present.

Signed-off-by: David Daney <david.daney@cavium.com>
diff --git a/arch/mips/pci/pci-octeon.c b/arch/mips/pci/pci-octeon.c
index 8eb2ee3..5b5ed76 100644
--- a/arch/mips/pci/pci-octeon.c
+++ b/arch/mips/pci/pci-octeon.c
@@ -705,7 +705,8 @@
 	 */
 	cvmx_write_csr(CVMX_NPI_PCI_INT_SUM2, -1);
 
-	if (IS_ERR(platform_device_register_simple("co_pci_edac", 0, NULL, 0)))
+	if (IS_ERR(platform_device_register_simple("octeon_pci_edac",
+						   -1, NULL, 0)))
 		pr_err("Registation of co_pci_edac failed!\n");
 
 	octeon_pci_dma_init();