vkGetPhysicalDeviceImageFormatProperties() tests whether format supports MSAA.
vkCreateRenderPass() validate each attachment supports format capabilities required
by each subpass that uses it.
vkCmdResolveImage() validate that destination attachment supports being resolved to.
MVKPixelFormats add getVkFormatCapabilities(), getMTLPixelFormatCapabilities(),
and vkFormatIsSupportedOrSubstitutable().
Rework type handling in flag functions in MVKFoundation.h.