fixed SPIR-V interface variable declarations

Bug: skia:
Change-Id: Ibdc975d8be672f00e30aab055358d8fe0e47e0c2
Reviewed-on: https://skia-review.googlesource.com/157222
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
1 file changed