Fixed FreeBSD/mips MALTA support for QEMU

Recource management functions in GT PCI controller driver
treated memory/IO resources as KSEG1 addresses, later during
activation these values would be increased by KSEG1 base again
rendering the address invalid and causing "bus error" trap.

Actual logic was converted to use real physical addresses,
so mapping takes place only during activation.

Submitted by: Aleksandr Rybalko <ray@FreeBSD.org>
Approved by: re (gjb)