In order to allow the use of PCIe cards such as graphics cards, whose
demands for BAR space are typically much higher than those of network
or SATA/USB cards, reconfigure the I/O windows so we can declare two
MMIO PCI regions: a 512 MB MMIO32 one at 0xc000_0000 and a 4 GB MMIO64
one at 0x8_0000_0000. In addition, this will leave ample room for an
ECAM config space at 0xe000_0000 (up to the ECAM maximum of 256 MB)

For compatibility with older kernels or firmware, leave the original
16 MB window in place as well.

Change-Id: Ia8177194e542078772f90941eced81b231c16887
Signed-off-by: Marcin Wojtas <mw@semihalf.com>
Reviewed-by: Kostya Porotchkin <kostap@marvell.com>