Remove TARGET_ROOT_OUT_SBIN / TARGET_ROOT_OUT_SBIN_UNSTRIPPED

/sbin was traditionally used for static binaries on the ramdisk for
Android, but now everything is a shared binary, so this directory is
empty and we do not want to encourage creation of new libraries in
this directory.

Bug: 73660730
Test: build
Change-Id: Ia82d892adfffb6fa325d0c570ae7999e7bb28dc2