Fix code generation for 16-bit block moves

[dmondrik]

What does this Pull Request accomplish?

• It fixes code generation for 16-bit block moves. The previously generated code just casted the buffer pointer, which is wrong.
• It includes the latest function metadata exported from scrapigen.

Why should this Pull Request be merged?

• Writing a buffer using a 16-bit array as an input parameter can be auto generated easily. There were other instances where it performed this for ViInt16[] so I just added ViUInt16[] to those cases.
• Reading a buffer using a 16-bit array as an output parameter is not a case that had been considered. Chatting with Ryan, it doesn't feel there would be sufficient reuse to warrant handling it in code generation. So I moved that method to the custom service code.

What testing has been done?

We plan to add auto tests in a follow-on PR for these and other register based methods. Hopefully that will be OK.