riscv: dts: canaan: fix bus {ranges,reg} warnings

riscv: dts: canaan: fix bus {ranges,reg} warnings

The k210 devicetrees warn about missing/empty reg and/or ranges
properties:
arch/riscv/boot/dts/canaan/k210.dtsi:408.22-460.5: Warning (unit_address_vs_reg): /soc/bus@52000000: node has a unit name, but no reg or ranges property
arch/riscv/boot/dts/canaan/k210.dtsi:352.22-406.5: Warning (simple_bus_reg): /soc/bus@50400000: missing or empty reg/ranges property

Add a ranges properties that naively caps the buses after the
allocation of their last devices.

Tested-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220705215213.1802496-12-mail@conchuod.ie
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>