Make shadowmappingomni demo spec compliant.
Make shadowmappingomni demo spec compliant.

It's illegal to use the same renderpass for rendering to a framebuffer
with different format (the offscreen one in this case). Added a
prepareOffscreenRenderpass function that creates a new renderpass with
the correct formats, and changed the vkCreateGraphicsPipelines and
vkCreateFramebuffer calls to use this one.

ming4883/Vulkan,jpbruyere/Vulkan,grim210/Vulkan,SaschaWillems/Vulkan,SaschaWillems/Vulkan,ming4883/Vulkan,SaschaWillems/Vulkan,SaschaWillems/Vulkan,dreadwords/Vulkan,martty/Vulkan,jpbruyere/Vulkan,grim210/Vulkan,ming4883/Vulkan,SaschaWillems/Vulkan