pci: Split low-level pci code from higher-level 'struct pci_device' code

Split pci.c into pci.c and pcidevice.c.  The low-level code that
interacts directly with the PCI devices remains in pci.c, while
functions dealing with the higher level pci_device cache move to
pcidevice.c.  Only pci.c is needed in 16bit mode.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
diff --git a/Makefile b/Makefile
index cbe9454..b0eb239 100644
--- a/Makefile
+++ b/Makefile
@@ -38,7 +38,7 @@
 SRC16=$(SRCBOTH)
 SRC32FLAT=$(SRCBOTH) post.c e820map.c malloc.c romfile.c x86.c optionroms.c \
     pmm.c font.c boot.c bootsplash.c jpeg.c bmp.c tcgbios.c sha1.c \
-    hw/ahci.c hw/pvscsi.c hw/usb-xhci.c hw/usb-hub.c hw/sdcard.c \
+    hw/pcidevice.c hw/ahci.c hw/pvscsi.c hw/usb-xhci.c hw/usb-hub.c hw/sdcard.c \
     fw/coreboot.c fw/lzmadecode.c fw/multiboot.c fw/csm.c fw/biostables.c \
     fw/paravirt.c fw/shadow.c fw/pciinit.c fw/smm.c fw/smp.c fw/mtrr.c fw/xen.c \
     fw/acpi.c fw/mptable.c fw/pirtable.c fw/smbios.c fw/romfile_loader.c \