[HLSL] Option for treat all textures as texture arrays.

d3d does not provide the ability to specify an array slice when creating a non-arrayed texture view from an arrayed texture. If hlsl will treat all textures as texture arrays, the d3d limitation can be bypassed since I can always create an arrayed view with a single array slice:

d3d_view_desc->Dimension = TextureArray;
d3d_view_desc->TextureArray.MostDetailedMip = mip_level;
d3d_view_desc->TextureArray.MipLevels = mip_level_count;
d3d_view_desc->TextureArray.FirstArraySlice = array_slice;
d3d_view_desc->TextureArray.ArraySize = 1;

Start by tracing how SPIRV-Cross represents HLSL textures and views, then compare that path with the d3d_view_desc->TextureArray fields described in the issue. Determine the design needed for an option that treats every texture as an array, and define completion as supporting single-slice arrayed views without breaking existing texture handling.