fsl-layerscape: Kconfig: Select RESV_RAM if GIC_V3_ITS

The GIC redistributor tables initialization depends on RESV_RAM config,
so select RESV_RAM if GIC_V3_ITS is enabled.

Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Reviewed-by: Wasim Khan <wasim.khan@nxp.com>
Signed-off-by: Priyanka Jain <priyanka.jain@nxp.com>