Fix potential memory leaks am: 6282064641

Original change: https://android-review.googlesource.com/c/platform/system/libufdt/+/2320803

Change-Id: I1500a346aba79c1c208c2fbf3876653fce47c532
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>