Result of running IWYU (https://include-what-you-use.org/) and
applying most of the suggestions about unncessary includes and
forward declarations.
Was motivated by observing that <thread> was being included in
ppcopcodes.cpp even though it was unused (found while researching
the use of threads), but seems generally good to help with build
times and correctness.
While dingusppc only emulates 32-bit Macs (for now), it is possible for a 32-bit Power Mac to use a PCIe card that has 64-bit BARs.
finish_config_bars is added to scan the cfg values of the BARs and determine their type. The type is stored separately so that it does not need to be determined again.
The type can be I/O (16 or 32 bit) or Mem (20 or 32 or 64 bit). A 64 bit bar is two BARs, the second contains the most significant 32 bits.
set_bar_value uses the stored type instead of trying to determine the type itself. It is always called even when the firmware is doing sizing. For sizing, It does the job of setting the bar value so do_bar_sizing is now just a stub.
Every PCIDevice that has a BAR needs to call finish_config_bars after setting up the cfg values just as they need to setup the cfg values. Since they need to do both, maybe the cfg values should be arguments of finish_config_bars, then finish_config_bars() should be renamed config_bars().
