soc: imx: gpcv2: include linux/sizes.h

This header is included indirectly on arm/arm64 but not on x86 so
CONFIG_COMPILE_TEST breaks. Fix by including <linux/sizes.h> directly.

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>