soc: fsl: qbman: Remove RESERVEDMEM_OF_DECLARE usage

soc: fsl: qbman: Remove RESERVEDMEM_OF_DECLARE usage

There is no reason to use RESERVEDMEM_OF_DECLARE() as the initialization
hook just saves off the base address and size. Use of
RESERVEDMEM_OF_DECLARE() is reserved for non-driver code and
initialization which must be done early. For qbman, retrieving the
address and size can be done in probe just as easily.

Link: https://lore.kernel.org/r/20240201192931.1324130-1-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>