ARM: dts: rcar-gen2: Fix PCI high address in interrupt-map-mask

"make dtbs_check" emits warnings like:

    pci@ee090000: interrupt-map-mask:0:0: 65280 is greater than the maximum of 63488
    pci@ee0b0000: interrupt-map-mask:0:0: 65280 is greater than the maximum of 63488
    pci@ee0d0000: interrupt-map-mask:0:0: 65280 is greater than the maximum of 63488

According to dt-schemas/schemas/pci/pci-bus.yaml, the PCI high address
cell value in the "interrupt-map-mask" property must lie in the range
0..0xf800.

Fix this by correcting the values from 0xff00 to 0xf800 in all affected
R-Car Gen2 and RZ/G1 DTS files.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20191213162459.1731-1-geert+renesas@glider.be