fixed a few SPIR-V generation errors

Bug: skia:
Change-Id: Ica79d36e32dcfbfc68a6238c9fa0b2a8dcfa20bb
Reviewed-on: https://skia-review.googlesource.com/78040
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
2 files changed