Fix includes of SkImageEncoder_NDK

Follow-up to https://skia-review.googlesource.com/c/skia/+/565005

Change-Id: I2c9c4a060619ece999500246fcdd5112808267ff
Bug: skia:13052
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/568796
Reviewed-by: Ben Wagner <bungeman@google.com>
2 files changed