ARM: exynos_defconfig: Enable thermal emulation for Exynos TMU

Enabling thermal emulation on Exynos SoCs. New sysfs attribute
- emul_temp is created.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>