inmates: pci: include feature check in capability lookup

Do not look for pci capabilites in devices that do not support them.

Signed-off-by: Henning Schild <henning.schild@siemens.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
README: Trivial adjustment to new hypervisor binary file names

There is now jailhouse.bin, jailhouse-intel.bin and jailhouse-amd.bin...

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
TODO: add an item for potential inter-cell information leaking

as discussed on the list
http://article.gmane.org/gmane.linux.jailhouse/1922

Signed-off-by: Henning Schild <henning.schild@siemens.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>