Create buffer for bone matrices

gpu.h

@@ -37,6 +37,9 @@ typedef struct {
 	VkBuffer mvp_buffer;
 	VkDeviceMemory mvp_buffer_mem;
 	mvp_t *mvps;
+	VkBuffer bone_matrix_buffer;
+	VkDeviceMemory bone_matrix_buffer_mem;
+	mat4_t *bone_matrices;
 	VkPipelineLayout pipeline_layout;
 	VkRenderPass render_pass;
 	VkPipeline pipeline;