layers: GH7, Fix bad var names in swapchain layer
layers: GH7, Fix bad var names in swapchain layer

Change-Id: I46331c530654334abacbfb3ffd3656809f6b7d5d

Radamanthe/VulkanSamples,critsec/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers,elongbug/Vulkan-LoaderAndValidationLayers,elongbug/Vulkan-LoaderAndValidationLayers,Radamanthe/VulkanSamples,critsec/Vulkan-LoaderAndValidationLayers,Radamanthe/VulkanSamples,KhronosGroup/Vulkan-LoaderAndValidationLayers,critsec/Vulkan-LoaderAndValidationLayers,elongbug/Vulkan-LoaderAndValidationLayers,critsec/Vulkan-LoaderAndValidationLayers,Radamanthe/VulkanSamples,Radamanthe/VulkanSamples,KhronosGroup/Vulkan-LoaderAndValidationLayers,Radamanthe/VulkanSamples,elongbug/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers