remove unneeded SK_LEGACY_BLITTER_CHOICE flag

Change-Id: If49be9fb6eac9b2af40898313e000855604be9f3
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/295829
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
1 file changed