This capability tracks whether memory-backend-file has
"x-use-canonical-path-for-ramblock-id" attribute. Introduced into
QEMU by commit fa0cb34d2210cc749b9a70db99bb41c56ad20831. As of
QEMU commit 8db0b20415c129cf5e577a593a4a0372d90b7cc9 the property
is considered stable by qemu despite the 'x-' prefix to preserve
compatibility with released qemu versions.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
