layers: Update behavior for secondary cmdbuffers w/ *_SIMULTANEOUS_USE_BIT set
layers: Update behavior for secondary cmdbuffers w/ *_SIMULTANEOUS_USE_BIT set

Spec clarification has been approved and secondary command buffers with
VK_COMMAND_BUFFER_USAGE_SIMULTANEOUS_USE_BIT may be in flight in multiple primary
command buffers at the same time.

This changes updates the error concerning secondary command buffers to be in-flight
on multiple primary command buffers to only appli if
VK_COMMAND_BUFFER_USAGE_SIMULTANEOUS_USE_BIT is not set.

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