Merge "Do not add non-existing -Bprebuilts/gcc/.../bin" am: 70387c5d am:...

Merge "Do not add non-existing -Bprebuilts/gcc/.../bin" am: 70387c5d am: 1918a612 am: a59f62bf

Original change: https://android-review.googlesource.com/c/platform/build/soong/+/1987029

Change-Id: I6086e708fab979e2f864997e087f2e5dc2e18af6