Make outout of cppbor::parse safely mutable am: 1a288db757 am: 69d2206312

Original change: https://android-review.googlesource.com/c/platform/system/libcppbor/+/2468182

Change-Id: I2320574766d4f5b9612df62065facadc494988a1
Signed-off-by: Automerger Merge Worker <[email protected]>