MIPS: Set io_map_base for several PCI bridges lacking it

Several MIPS platforms don't set pci_controller::io_map_base for their
PCI bridges.  This results in a panic in pci_iomap().  (The panic is
conditional on CONFIG_PCI_DOMAINS, but that is now enabled for all PCI
MIPS systems.)

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: linux-mips@linux-mips.org
Cc: Martin Michlmayr <tbm@cyrius.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: 584784@bugs.debian.org
Patchwork: https://patchwork.linux-mips.org/patch/1377/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/pci/ops-pmcmsp.c

@@ -944,6 +944,7 @@ static struct pci_controller msp_pci_controller = {
 	.pci_ops	= &msp_pci_ops,
 	.mem_resource	= &pci_mem_resource,
 	.mem_offset	= 0,
+	.io_map_base	= MSP_PCI_IOSPACE_BASE,
 	.io_resource	= &pci_io_resource,
 	.io_offset	= 0
 };