GIC_ITS used in AM654 platform has the same configuration as that of
GIC_ITS used in Socionext SoCs. Add "socionext,synquacer-pre-its"
property to get PCI MSI working.
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com> Signed-off-by: Tero Kristo <t-kristo@ti.com>