MIPS: BMIPS: Update defconfig

Ran "make savedefconfig" to bring bmips_stb_defconfig up to date.

Signed-off-by: Markus Mayer <mmayer@broadcom.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>