Remove dangling semicolons in cpp outputs am: 3d46cc7134 am: bccc01a3ff am: d15d50d369

Original change: https://android-review.googlesource.com/c/platform/system/tools/aidl/+/1688283

Change-Id: I2c486a5f23f21cbe0a23e538fbb4f61b5c2d0698