And also changed "serialis-" to "serializ-", mostly choosing the "z" version because it's what's being used in the function names. It's also the version closer to the original Greek suffix, so I hope it will make @zfigura happier.
Well, I grew up in Europe, so I was thought the proper -ise spelling. The spelling of vkd3d_shader_serialize_dxbc() was mostly dictated by the rather unfortunate precedent set by vkd3d_shader_serialize_root_signature(). ;)