Allow allocation of non-coherent memory if coherency is not required.

Allow allocation of non-coherent memory if coherency is not required.

Use MemoryRequirement instead of VkMemoryProperty flags as allocation
requirement. This allows specifying memory that is allowed to be
coherent but it is not required. This is not possible with the vk mask
since in vulkan non-coherence (instead of coherence) is a feature
of the memory.

Change-Id: Iab50a6264599c8c50f4c5008e95b9c9429d264db