Setting the wrong alignment value when loading a Buffer Reference through a Buffer Reference

https://godbolt.org/z/j8jGvsnMh

```glsl
layout(buffer_reference) buffer S4;

layout(buffer_reference, buffer_reference_align = 8, std430) readonly buffer S3 {
S4 e;
};

// Set buffer_reference_align to 8 and it generates valid code
layout(buffer_reference, buffer_reference_align = 4, std430) readonly buffer S4 {
uint f;
};

void main() {
S3 x;
S4 y = x.e;
}
```

Seems currently glslang sets the `x.e` as an `OpLoad` with a result type of `OpTypePointer` but the `Aligned 4` is wrong and should be `8` and produces a spirv-val error (https://godbolt.org/z/sxT1asEdv)

Start with the GLSL reproducer in the Godbolt link and inspect the generated SPIR-V for the OpLoad of x.e. Compare its alignment operand with the buffer_reference_align values, then validate the output with spirv-val. Done means the generated load uses alignment 8 and the validator accepts the result.

Written by the indexing model from the issue text.