Remove RG32F color type and pixel config.

Change-Id: I7fd3a8f6c02217d011f353ef602718a537bb87b2
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/228116
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
18 files changed