MIPS: Loongson64: Remove not used pci.c

After commit 6423e59a ("MIPS: Loongson64: Switch to generic PCI
driver"), arch/mips/loongson64/pci.c is not used any more, remove it.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/loongson64/pci.c

-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Copyright (C) 2007 Lemote, Inc. & Institute of Computing Technology
- * Author: Fuxin Zhang, zhangfx@lemote.com
- */
-#include <linux/pci.h>
-
-#include <pci.h>
-#include <loongson.h>
-#include <boot_param.h>
-
-static struct resource loongson_pci_mem_resource = {
-	.name	= "pci memory space",
-	.start	= LOONGSON_PCI_MEM_START,
-	.end	= LOONGSON_PCI_MEM_END,
-	.flags	= IORESOURCE_MEM,
-};
-
-static struct resource loongson_pci_io_resource = {
-	.name	= "pci io space",
-	.start	= LOONGSON_PCI_IO_START,
-	.end	= IO_SPACE_LIMIT,
-	.flags	= IORESOURCE_IO,
-};
-
-static struct pci_controller  loongson_pci_controller = {
-	.pci_ops	= &loongson_pci_ops,
-	.io_resource	= &loongson_pci_io_resource,
-	.mem_resource	= &loongson_pci_mem_resource,
-	.mem_offset	= 0x00000000UL,
-	.io_offset	= 0x00000000UL,
-};
-
-
-extern int sbx00_acpi_init(void);
-
-static int __init pcibios_init(void)
-{
-
-	loongson_pci_controller.io_map_base = mips_io_port_base;
-	loongson_pci_mem_resource.start = loongson_sysconf.pci_mem_start_addr;
-	loongson_pci_mem_resource.end = loongson_sysconf.pci_mem_end_addr;
-
-	register_pci_controller(&loongson_pci_controller);
-
-	return 0;
-}
-
-arch_initcall(pcibios_init);