Merge "libfdt: Make Fdt::root{,_mut}() infallible" into main am: 5e996daec7

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Virtualization/+/2967462

Change-Id: Ia1fe47dd5e407bd4f84c15733ccbf29fa4b8f012
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>