[graphite] Add alignment directives to IntersectionTree arrays

Thise should have been aligned properly already due to their
placement, but it doesn't hurt to make it more explicit.

Change-Id: Idb6a03e93d86df7727324987f166d197d5e708a4
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/461377
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Herb Derby <herb@google.com>
1 file changed