Remove simple GrGpu::createTexture helper

Change-Id: I8ad3213517594987ac604f4c08086778254b5a7b
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/228062
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
5 files changed