Random conditionals are not supported in Android.bp files, so this
needed a build system extension in Go.

/system/xbin is deprecated, this now installs into /system/bin and adds
a CleanSpec.mk entry to remove the old version.

See build/soong/README.md for more information.

Test: cd tools/security/sanitizer-status; mma
Test: SANITIZE_TARGET=address m libsanitizer-status
Test: SANITIZE_TARGET="address coverage" m libsanitizer-status
Change-Id: Iabc92d580bb76dfb7272afc57e26bd0595990596