-fno-diagnostics-show-caret

clang complains about:

aarch64-poky-linux-clang++: error: unknown argument: '-fno-diagnostics-show-caret'

Workaround:

local.conf

    CXXFLAGS:remove:pn-clang:toolchain-clang = "-fno-diagnostics-show-caret"
    CFLAGS:remove:pn-clang:toolchain-clang = "-fno-diagnostics-show-caret"

There is a similar option for clang: -fno-caret-diagnostics, so ''icecc.bbclass' should be fixed in future.