Fix naming according to the Rust styleguide. am: 192e0bbc0f am: 8ffaf612d8 am: c9ff797679 am: 9764ff1303

Original change: https://android-review.googlesource.com/c/platform/system/tools/sysprop/+/2743333

Change-Id: I4457576c829eb2982c25b9e56477c2e82204c2ac
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>