zink: fix zink_resource_access_is_write()

this was accurately returning whether the access had only write flags,
but it was incorrectly returning false for READ|WRITE

cc: mesa-stable

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21583>
(cherry picked from commit 5be506c16ece8c62b84e21a625db9d36bc489982)
2 files changed