Only clear system_shared_libs when building for bionic am: 74985fcc am: 293b5a5b am: c4df296a

Original change: https://android-review.googlesource.com/c/platform/external/arm-optimized-routines/+/1968802

Change-Id: Ic164f1288a411faf97d4071db1b1daf1b0bd2c27