PCI: alpha: use generic pci_enable_resources()

Use the generic pci_enable_resources() instead of the arch-specific code.

Unlike this arch-specific code, the generic version:
    - skips resources unless requested in "mask"
    - skips ROM resources unless IORESOURCE_ROM_ENABLE is set
    - checks for resource collisions with "!r->parent"

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>