If not pinned VMA can become an eviction target just before it needs to be
executed which breaks the internal object lifetime rules.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=87399Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>