ARM: dts: Update rpi-400 and cm4 dts to match 4-b

The Pi 4B dts file has had numerous updates since the Pi 400 and CM4
dts files were written. Apply those updates to the other files to
minimise the differences. The change is largely cosmetic, except for
the PCI "device-type" to "device_type" rename, and the correction of
the labels on the Pi 400 GPIO expander pins.

Signed-off-by: Phil Elwell <phil@raspberrypi.com>