squash! d3d12: setup D3D12_VERTEX_BUFFER_VIEW-struct when binding buffers
d3d12: Only submit vertex buffers that have a resource attached
The active vertex buffers are actually identified by a mask that is set based on whether a resource is attached, but the count of the number of vertex buffers is set based on the last bit set in this mask. Consequently, only set the vbo resource data for the vertex buffers that are active.
Closes: #66
Edited by Gert Wollny