[dev][bus][pci] major refactor of the PCI bus driver

-Add a bus manager level, which is an object oriented walk of the pci
busses to build a per device object for later manipulation.
-Add features to enable MSI interrupts.
-Extend generic interrupt api to allow the platform to allocate vectors
for MSI interrupts.
-Rearrange a bit of the pc platform for the platform api changes.
-Add PC platform support for using the local apic to EOI MSI vectors.
-Fix up a few existing PCI drivers for small API changes.
-Add a few stubbed out routines for non PC platforms that use PCI.

platform/pc/platform_p.h

@@ -16,3 +16,13 @@ void platform_init_debug(void);
 void platform_init_interrupts(void);
 void platform_init_timer(void);
 
+// legacy programmable interrupt controller
+void pic_init(void);
+void pic_enable(unsigned int vector, bool enable);
+void pic_eoi(unsigned int vector);
+void pic_mask_interrupts(void);
+
+// local apic
+void lapic_init(void);
+void lapic_eoi(unsigned int vector);
+