MSL: Unsized array of images is not supported in MSL

We are converting HLSL to SPIR-V using DXC and then SPIR-V to MSL with SPIRV-Cross. We are getting an error msg `Unsized array of images is not supported in MSL.` Though it should be supported if SPIRV-Cross has support for Metal Argument Buffers and Bindless.

For debugging, I converted the SPIR-V to VK glsl. And it seems this line is causing the problem
`layout(set = 30, binding = 0) uniform texture2D CommonBindlessResources_textures[];`

The original HLSL line was
`Texture2D CommonBindlessResources_textures[] : register(t0 , space30 ); `

As far as I understand the MSL conversion should be something like:

```
struct CommonBindlessResources_texturesStruct
{
texture2d textures;
};

pixelShaderEntryPoint(CommonBindlessResources_texturesStruct* CommonBindlessResources_textures [[buffer(0)]])
{

}
```

We are compiling spirv to msl with following options:
```
spirv_cross::CompilerMSL::Options options;
options.platform = spirv_cross::CompilerMSL::Options::Platform::iOS;
options.msl_version = spirv_cross::CompilerMSL::Options::make_msl_version(2, 3);
options.ios_use_simdgroup_functions = true;
options.ios_support_base_vertex_instance = true;
options.enable_decoration_binding = true;
options.texture_buffer_native = true;
options.argument_buffers = true;
```

Any ideas what's wrong? Will I have to modify spirv-cross and add support for this conversion?

Reproduce the conversion with the supplied HLSL resource declaration, SPIR-V GLSL output, and CompilerMSL options, focusing on argument_buffers and MSL 2.3. Read the MSL compiler's handling of unsized image arrays and compare the generated result with the requested argument-buffer structure; done means establishing whether this case is supported and identifying the required project change or limitation.

Written by the indexing model from the issue text.