PCI devices on 64 bit systems can be mapped anywhere, not just in the
lower 4G of memory. Remove pointer size assumptions.
Also this removes the use of a struct uart_device_config to store the
(runtime) BAR address. That struct has other stuff in it, and the
only thing we need is the single MMIO address. It's also REALLY
confusing to have two "devconf" fields in the device storing values of
the same struct type, some fields of which are used from one of them
but some from the other!
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
