ARM: dts: r8a779x: Fix PCI bus dtc warnings

The bogus 'device_type = "pci"' confuses dtc, causing lots of totally
unrelated warnings.  After fixing that, real warnings like

    arch/arm/boot/dts/r8a7790-lager.dtb: Warning (pci_device_reg): Node /pci@ee090000/usb@0,1 PCI unit address format error, expected "1,0"

are left.  Correct the unit-addresses and reg properties of the subnodes
to fix these.

Signed-off-by: Rob Herring <robh@kernel.org>
[geert: Improve description]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>