[graphite] Fix ContextOptions.h #includes

Change-Id: I73f4273c1617e853b36a36700e014f3acac5a22c
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/946056
Reviewed-by: Nicolette Prevost <nicolettep@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
1 file changed