Bug 21730 - Make abipkgdiff compare Linux Kernel packages as expected

Bug 21730 - Make abipkgdiff compare Linux Kernel packages as expected

This is the initial patch that makes abipkgdiff recognize Linux kernel
packages passed in argument and do the right thing.

abipkgdiff gets the vmlinux binary from the debug info package,
considers the union of that vmlinux binary and the thousands of kernel
modules that we shall name "the Kernel".  It then compares ABI
(actually Kernel/Module Interface, a.k.a KMI) of the Kernel of the
first package against the KMI of the Kernel of the second package.

	* include/abg-tools-utils.h (get_vmlinux_path_from_kernel_dist):
	Declare new function.
	(get_binary_paths_from_kernel_dist): Re-organize order of
	parameters.
	(file_is_kernel_package, file_is_kernel_debuginfo_package): Make
	the file_path parameter be const.
	(build_corpus_group_from_kernel_dist_under): Take an additional
	debug_info_root parameter.
	* src/abg-tools-utils.cc (file_is_kernel_package)
	(file_is_kernel_debuginfo_package): Const-ify the file_name
	parameter.
	(find_vmlinux_path): Define new static function.
	(get_binary_paths_from_kernel_dist): Re-organize the order of
	parameters.  The debug_info_root_path parameter is now an input
	parameter.
	(get_vmlinux_path_from_kernel_dist): Define new function.
	(get_binary_paths_from_kernel_dist): Adjust invocation of
	get_binary_paths_from_kernel_dist.
	(build_corpus_group_from_kernel_dist_under): Take an additional
	debug_info_root parameter.
	* tools/abidw.cc (load_kernel_corpus_group_and_write_abixml):
	Adjust invocation to build_corpus_group_from_kernel_dist_under.
	* tools/abipkgdiff.cc (create_maps_of_package_content):  Don't map
	the content of a Linux Kernel package.
	(compare_prepared_userspace_packages)
	(compare_prepared_linux_kernel_packages, compare_prepared): Define
	new functions.
	(compare): Use the new functions above here.
	* tools/kmidiff.cc (print_kernel_dist_binary_paths_under): Adjust
	the invocation of get_binary_paths_from_kernel_dist.
	(main): Adjust the invocation of
	build_corpus_group_from_kernel_dist_under.  Make sure that a
	kernel package is accompanied by a debug info package.

Signed-off-by: Dodji Seketeli <dodji@redhat.com>