r341812 enabled only arm target support in LLVM on arm and armv6,
because ld.bfd 2.17.50 lacked support for range extensions required for
linking such large binaries/libraries. r341812 indicated that the
workaround should be removed once the userland can be linked by lld.
r354289 switched armv6 to use lld by default, so remove the workaround
on armv6. The workaround remains in place for arm (v5), and will
presumably be removed when arm is retired.
Sponsored by: The FreeBSD Foundation
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