Parse SPIR-V row-major matrices

[kvark]

Our IR is column-major only. There is currently code in SPV-in fn parse_type_matrix to check for this:

if let Some(Decoration {
            matrix_major: Some(ref major),
            ..
        }) = decor
        {
            match *major {
                Majority::Column => (),
                Majority::Row => return Err(Error::UnsupportedRowMajorMatrix),
            }
        }

However, it never fires up, because the decoration is actually expected on a struct member instead of the type.
The same applies to matrix stride. They both are not correctly handled in SPV-in.
Here is an example dump from 215.spv:

               OpMemberDecorate %_struct_1504 0 RowMajor
               OpMemberDecorate %_struct_1504 0 Offset 0
               OpMemberDecorate %_struct_1504 0 MatrixStride 16
               OpMemberDecorate %_struct_1504 1 Offset 304
               OpMemberDecorate %_struct_1504 2 Offset 320
               OpMemberDecorate %_struct_1504 3 Offset 400
               OpMemberDecorate %_struct_1504 4 Offset 704

This is blocking #409

I think the idea on how this should be handled is to try to avoid translating it, unless necessary.
I.e. vector multiplication by a matrix can just switch the order in order to account for this, and it's possible that this is enough.