[MIPS] Alchemy: fix PCI resource conflict

... by getting the PCI resources back into the 32-bit range -- there's no
need therefore for CONFIG_RESOURCES_64BIT either. This makes Alchemy PCI
work again while currently the kernel skips the bus scan.

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>