Merge "Add README and update script for Trusty" into main am: 6e7a30c27b am: 973abd9f3e

Original change: https://android-review.googlesource.com/c/platform/prebuilts/android-emulator/+/3107204

Change-Id: Ibe01debb76019d3627d15e7fe603be85bdfc39db
Signed-off-by: Automerger Merge Worker <[email protected]>