The imx SC api strongly assumes that messages are composed out of
4-bytes words but some of our message structs have odd sizeofs.

This produces many oopses with CONFIG_KASAN=y.

Fix by marking with __aligned(4).

Fixes: a3094fc1 ("rtc: imx-sc: add rtc alarm support")
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Link: https://lore.kernel.org/r/13404bac8360852d86c61fad5ae5f0c91ffc4cb6.1582216144.git.leonard.crestez@nxp.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>