The libvirt/ directory is a bit cluttered. Move xml files to a
subdirectory.
Test plan:
PASS: Regression for default and mad examples
PASS: unit test of the affected replacement values for all
configurations
Story: 2010816
Task: 48613
Change-Id: I7a8552616cce9ac4639d3c2c67d5a019f7f06bdc
Signed-off-by: Michel Thebeau <michel.thebeau@windriver.com>