kernel code test: add comment in __request_resource()
kernel code test: add reserve_region_with_split_test()
kernel code test: add one flag when print resource
kernel code test: iterative version of __reserve_region_with_split()
kernel code test: change the test case for list

1. change the index from [0-9] to [1-10]
2. initialize the list in the beginning of list_first_entry_test()
kernel code test: add list_next_entry()
kernel code test: add list_is_first()
kernel code test: fix bug in list_next_entry_test()

list_next_entry() will iterate on the list. When it iterate on the last node,
the next one would be the head, which is a dummy node.

So we need to check whether next one is the head or not.
kernel code test: pci_bus_get_depth2() another iterative version
kernel code test: another version of pci_hierachy_setup1()

In ordre to test the pci_get_max_depth(), it need different pci_bus
architecture.

This function create another pci tree structure.
kernel code test: remove revisit check in pci_bus_get_depth2()

Since we use the node to check whether it hit the head again or not, there is
no need to set/check the revisit value.

This patch just clean this.
kernel code test: cleanup pci_bus_get_depth2()
kernel code test: move the pci chart close to the function
kernel code test: another version of pci tree
kernel code test: create another pci tree
kernel code test: create debugfs example