Revert "ARM: 9070/1: Make UNWINDER_ARM depend on ld.bfd or ld.lld 11.0.0+"

This reverts commit 7411cfc3.

The minimum supported version of LLVM has been raised to 11.0.0, meaning
this check is always true, so it can be dropped.

Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>