Remove GrFP iter declarations and comments

Accidentally left these behind in previous change.

Change-Id: I77620d27561ce1c73b9509388cd9253c405a95b6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/436997
Commit-Queue: Brian Salomon <bsalomon@google.com>
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
Auto-Submit: Brian Salomon <bsalomon@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
1 file changed