The new pci code is moved to port/pci.[hc] and shared by
all ports.
Each port has its own PCI controller implementation,
providing the pcicfgrw*() functions for low level pci
config space access. The locking for pcicfgrw*() is now
done by the caller (only port/pci.c).
Device drivers now need to include "../port/pci.h" in
addition to "io.h".
The new code now checks bridge windows and membars,
while enumerating the bus, giving the pc driver a chance
to re-assign them. This is needed because some UEFI
implementations fail to assign the bars for some devices,
so we need to do it outselfs. (See pcireservemem()).
While working on this, it was discovered that the pci
code assimed the smallest I/O bar size is 16 (pcibarsize()),
which is wrong. I/O bars can be as small as 4 bytes.
Bit 1 in an I/O bar is also reserved and should be masked off,
making the port mask: port = bar & ~3;
the max packet size is configured in 1K increments on these chips,
which can result in the card receiving a 10K packet but the
driver having only allocated 9.5K of buffer. this actually caued
pool corruption with i210, i217, i218, i219, i350.
for 82598 and x550, we explicitely round rbsz to avoid similar bugs
in the future, even tho the Rbsz constant was already a multiple of
1K and is not affected by the bug.