Add support for the UUID parameter to the emulated RTAS call
ibm,get-system-parameter.
Return the guest's UUID as the value for the RTAS UUID system
parameter, or null (a zero length result) if it is not set.
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>