Vulkan: Fix image base/max level respecification case. Bug: angleproject:6776 Change-Id: I3e7774c20bae6d7ad7b1775d46797104e2429b81 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3426208 Reviewed-by: Charlie Lao <cclao@google.com> Reviewed-by: Yuxin Hu <yuxinhu@google.com> Commit-Queue: Jamie Madill <jmadill@chromium.org>