anv: fix memory leak on device destroy

v2: handle vma destruction if vkCreateDevice fails (Jordan)

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Gitlab: https://gitlab.freedesktop.org/mesa/mesa/issues/1959


Cc: <mesa-stable@lists.freedesktop.org>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
(cherry picked from commit b30e01ae)