Remove libc++ from the musl sysroot am: 9f1ffdd3d9

Original change: https://android-review.googlesource.com/c/platform/external/musl/+/2676536

Change-Id: Ib0798fa84c3cb1d6a583560111b3d52a9637e055
Signed-off-by: Automerger Merge Worker <[email protected]>