Needed for cross-builds without --sysroot, where USE_LIBPATH isn't
set. See elf32.em after_open. Perhap ld ought to look at -rpath in
this case?
* testsuite/ld-elf/shared.exp: Add -rpath-link and -no-as-needed
to various tests.
* testsuite/ld-elfweak/elfweak.exp: Likewise.
* testsuite/ld-elfvers/vers.exp (vers19): Fix -rpath-link option.