arm64: PCI(e) arch support

This patch adds the arch support for PCI(e) for arm64. The files
added or modified in this patch are based on PCI(e) support in
32bit arm.

Change-Id: Ie274623b5bf053e63d8857d256cbf91fef80bcf4
Signed-off-by: Tanmay Inamdar <tinamdar@apm.com>
Signed-off-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Git-commit: 0dbd501893bc8b003be715b8320e520614bd8ae1
Git-repo: git://kernel.ubuntu.com/ubuntu/ubuntu-trusty.git


[yanhe@codeaurora.org: solve the minor compilation errors]
Signed-off-by: Yan He <yanhe@codeaurora.org>