Handle BUFFER_DYNAMIC and UPDATE_AFTER_BIND interaction

Handle BUFFER_DYNAMIC and UPDATE_AFTER_BIND interaction

"descriptorset_random" tests were violating the spec's requirement that
bindings with VK_DESCRIPTOR_BINDING_UPDATE_AFTER_BIND_BIT_EXT bit
cannot be used with BUFFER_DYNAMIC descriptor types in one set.
Testing of UPDATE_AFTER_BIND bindings is disabled
in order to conform to the requirement.

Fix validation of inline UBO with variable descriptor count

When used with variable descriptor count inline UBO's were read
and written out of allocated size, which is set in
VkDescriptorSetVariableDescriptorCountAllocateInfoEXT.descriptorCount

Components: Vulkan

Affects: dEQP-VK.binding_model.descriptorset_random.*

VK-GL-CTS issue: 1708

Change-Id: I9e97b701897961aedf8a746b72a1070ccd3b04e7