Adding METADATA file to toolchain-utils and refreshing the current version am: 9dc07341f9 am: d33de92dc9 am: c2cf8392f9

Original change: https://android-review.googlesource.com/c/platform/external/toolchain-utils/+/2290473

Change-Id: I44a3bba2d40809aa19dd70fa3991b5d9d3cc9b35
Signed-off-by: Automerger Merge Worker <[email protected]>