This patch adds initial support for compute shaders and SSBOs to
the vulkan backend. As the development is oriented to the test-
cases we have the implementation is limited to what is used there.

It has been validated that with this patch 2 test cases are running
as expected
- `GPUVulkanTest.gpu_shader_compute_ssbo`
- `GPUVulkanTest.gpu_storage_buffer_create_update_read`

This patch includes:
- Allocating VkBuffer on device.
- Uploading data from CPU to VkBuffer.
- Binding VkBuffer as SSBO to a compute shader.
- Execute compute shader and altering VkBuffer.
- Download the VkBuffer to CPU ram.
- Validate that it worked.

GHOST API has been changed as the original design was created before
we even had support for compute shaders in blender. The function `GHOST_getVulkanBackbuffer` has been separated to retrieve the command
buffer without a backbuffer (`GHOST_getVulkanCommandBuffer`). In order
to do correct command buffer processing we needed access to the queue
owned by GHOST. This is returned as part of the `GHOST_getVulkanHandles`
function.

@@ -50,2 +53,3 @@
+          vk_device, nullptr, 1, &pipeline_info, vk_allocation_callbacks, &vk_pipeline) !=
       VK_SUCCESS) {
-    return VKPipeline();
+    //return VKPipeline();

@@ -0,0 +112,4 @@
+    return 0;
+  }
+
+  size_t size_in_bytes() const

@@ -889,0 +926,4 @@
+  /* Add push constants to the descriptor when push constants are stored in a storage buffer.*/
+  const VKPushConstantsLayout &push_constants_layout = interface.push_constants_layout_get();
+  if (push_constants_layout.storage_type_get() ==
+      VKPushConstantsLayout::StorageType::STORAGE_BUFFER) {

@@ -1033,12 +1096,6 @@ std::string VKShader::vertex_interface_declare(const shader::ShaderCreateInfo &i
     ss << "layout(location = " << attr.index << ") ";
     ss << "in " << to_string(attr.type) << " " << attr.name << ";\n";
   }
-  /* NOTE(D4490): Fix a bug where shader without any vertex attributes do not behave correctly.

@@ -58,0 +80,4 @@
+    .push_constant(Type::FLOAT, "filler2", 32)
+    .do_static_compilation(true);
+
+/* It is expected that this shader will use uniform buffers and not push constants.*/

@@ -119,6 +137,10 @@ void VKDescriptorSet::update(VkDevice vk_device)
     descriptor_writes.append(write_descriptor);
   }
 
+  BLI_assert_msg(image_infos.size() + buffer_infos.size() == descriptor_writes.size(),

@@ -0,0 +40,4 @@
+    }
+  }
+
+  void generate_test_data(const float components_mul, const float component_mul)

@@ -0,0 +39,4 @@
+  static uint32_t array_components_len(const shader::Type type);
+};
+
+template<typename Layout> static uint32_t element_stride(const shader::Type type)

@@ -0,0 +228,4 @@
+     * bytes.*/
+    BLI_assert(sizeof(T) == 4);
+    const T *src = input_data;
+    for (const int i : IndexRange(array_size)) {

@@ -70,0 +70,4 @@
+  VKPushConstants &push_constants = pipeline.push_constants_get();
+
+  /* Update push constants based on their storage type.*/
+  switch (push_constants.layout_get().storage_type_get()) {