MIPS: PCI: Use pci_enable_resources()

pci-legacy.c under MIPS has a copy of pci_enable_resources() named as
pcibios_enable_resources(). Having own copy of same functionality could
lead to inconsistencies in behavior, especially now as
pci_enable_resources() and the bridge window resource flags behavior are
going to be altered by upcoming changes.

The check for !r->start && r->end is already covered by the more generic
checks done in pci_enable_resources().

Call pci_enable_resources() from MIPS's pcibios_enable_device() and remove
pcibios_enable_resources().

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Link: https://patch.msgid.link/20250829131113.36754-4-ilpo.jarvinen@linux.intel.com