arm64: exynos: Enable exynos-chipid driver

Enable Exynos Chipid driver for accessing SoC related information.

Link: https://lore.kernel.org/r/20190904175002.10487-6-krzk@kernel.org
Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>