dt-bindings: PCI: Remove fallback from Rockchip DesignWare binding

The snps,dw-pcie binds to a standalone driver. It is not fully
compatible with the Rockchip implementation and causes a hang if it
binds to the device.

Remove this binding as a valid fallback.

Link: https://lore.kernel.org/r/20220429123832.2376381-2-pgwipeout@gmail.com


Signed-off-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>