Backport of pci cardbus number enumeration from 2.6 to 2.4.29

Backport of pci cardbus number enumeration from 2.6 to 2.4.29

[Paul Marrons]

Hi Martin,

To overcome a problem with my laptop cardbus not being assigned the 
correct bus number in 2.4.29 (I originally did this change for 2.4.27) I 
backported a portion of the code in the 2.6 kernel drivers/pci/pci.c 
file. I did this because I noticed that only 2.6 assigned the correct 
bus number and I specifically need to run 2.4.X because of a driver I 
need that is not 2.6 compatible. Basically without this change on my 
laptop (Thinkpad 240) both the main PCI bus and cardbus bridge both get 
assigned bus#0 and as a result any cardbus devices present are not 
correctly detected and allocated any resources, in addition the 
/proc/bus/pci contains two '0' entries and tools such as lspci fail to 
work.

I am aware of people overcoming this problem (with my model of laptop) 
by setting defining pcibios_assign_all_busses() as 1. But this backport 
is a superior solution to the problem.

The few small changes are isolated to pci_add_new_bus and 
pci_scan_bridge. I hope you will be able to incorporate them into the 
next 2.4 kernel release.

If there is anything else I need to do please let me know.

Regards,

Paul Marrons.