[automerger skipped] libufdt: Fix possible null pointer access if test program is fed bad input. am: d68b0549f4 -s ours am: 1a9d855442 -s ours

am skip reason: Merged-In I4b9bb58037fc236852529c944d36c4e51e4c43fa with SHA-1 f9100fd2e8 is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/libufdt/+/20747473

Change-Id: I2fa0f68374ceaad391fbd8615c140101fb3a081f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>