Mike Blumenkrantz authored Feb 03, 2023 and Dylan Baker committed Feb 06, 2023

according to spec, the maximum number of acquired images can be calculated with

swapchain_size - VkSurfaceCapabilitiesKHR::minImageCount + 1

the previous calculation was both wrong and occurring in the wrong place,
so this corrects both issues

cc: mesa-stable

Part-of: <!21095>
(cherry picked from commit 89cf0a3b)