of: address: Remove duplicated functions

The recently added of_bus_default_flags_translate() performs the exact
same operation as of_bus_pci_translate() and of_bus_isa_translate().

Avoid duplicated code replacing both of_bus_pci_translate() and
of_bus_isa_translate() with of_bus_default_flags_translate().

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Link: https://lore.kernel.org/r/20231017110221.189299-3-herve.codina@bootlin.com
Signed-off-by: Rob Herring <robh@kernel.org>