x86: kconfig: Select USE_PRIVATE_LIBGCC

x86 is using the built-in libgcc implementation and this cannot be
turned off.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
21 files changed