mfd: cros_ec: add ec_align macros

To reduce code and improve performance of the embedded controller
firmware, pragma __aligned(2) or __aligned(4) are used when alignment to
16 or 32 bit boundary is expected.

Define all ec_align to packed when compiling kernel.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Benson Leung <bleung@chromium.org>
Reviewed-by: Fabien Lahoudere <fabien.lahoudere@collabora.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>