fsi: master-ast-cf: Use of_reserved_mem_region_to_resource for "memory-region"

Use the newly added of_reserved_mem_region_to_resource() function to
handle "memory-region" properties.

Signed-off-by: "Rob Herring (Arm)" <robh@kernel.org>
Reviewed-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20250703183439.2073555-1-robh@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>