i440fx-test: add test to compare default register values

This test compares all of the default register values against the
spec.  It turns out we deviate in quite a few places.  These
places are really only visible to the BIOS though which is why
this hasn't created any problems.

The deviation actually happens in the core PCI layer so I suspect
it's not a simple fix if we really care to fix it.  For now, just
disable the affected checks.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Message-id: 1366123521-4330-6-git-send-email-aliguori@us.ibm.com
