loader: Fix crash with null VkApplicationInfo
loader: Fix crash with null VkApplicationInfo

Fix a crash when creating an instance where
pCreateInfo->pApplicationInfo is set to null.

KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers