Set VK_NO_PROTOTYPES for vulkan backend

Bug: skia:
Change-Id: Id740efe6030b70271b0eb3a3bd6a111202f28fd8
Reviewed-on: https://skia-review.googlesource.com/69160
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Chris Dalton <csmartdalton@google.com>
1 file changed