kconfig: print recursive dependency errors in the parsed order

for_all_symbols() iterates in the symbol hash table. The order of
iteration depends on the hash table implementation.

If you use it for printing errors, they are shown in random order.

For example, the order of following test input and the corresponding
error do not match:
 - scripts/kconfig/tests/err_recursive_dep/Kconfig
 - scripts/kconfig/tests/err_recursive_dep/expected_stderr

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>