Remove extra GrSkSLFP constructor

Both Make() factories have a similar pattern now (sharing the simpler
constructor, and appending uniforms in the factory).

Change-Id: I362afd19c9fc0fa45f614df00c232a099ac16b4b
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/417597
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: Brian Osman <brianosman@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>
2 files changed