package/jailhouse: new package

Jailhouse is a partitioning Hypervisor based on Linux. It is able to run
bare-metal applications or (adapted) operating systems besides Linux.
For this purpose, it configures CPU and device virtualization features
of the hardware platform in a way that none of these domains, called
"cells" here, can interfere with each other in an unacceptable way.

For 32-bit ARM, it uses instructions from the armv7ve ISA. Since we
don't have a Config.in symbol to represent this yet, exclude 32-bit ARM
for now.

Signed-off-by: Carlo Caione <ccaione@baylibre.com>
[Arnout:
 - remove arm as supported architecture;
 - add architecture dependency to comment;
 - remove architecture comment;
 - move python dependencies to the condition.]
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>