Support swizzled out-params in SPIR-V intrinsic calls.

The code in writeFunctionCall which supported swizzled out-params has
been factored out into a pair of helper functions. The code for emitting
intrinsics now relies on these helpers when emitting out-params.

Change-Id: I4436185ae107d70b529e7e1ea0dd89f844c6a673
Bug: skia:11052
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/446719
Auto-Submit: John Stiles <johnstiles@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
4 files changed