Implement missing vertex element functions.

Change-Id: I54c54838b7140023d902d5cb615eb8509eb6e23a
Reviewed-on: https://swiftshader-review.googlesource.com/3800
Reviewed-by: Nicolas Capens <capn@google.com>
Tested-by: Nicolas Capens <capn@google.com>
1 file changed