Refactor get_cc_option so it is simpler and also does not fail
when using external toolchain.
(From OE-Core rev: d4564ee59df907d1e01a3610ac88a35f9a78c1ce)
Signed-off-by: Juro Bystricky <juro.bystricky@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>