hw/arm/xlnx-versal: ospi: refactor creation

hw/arm/xlnx-versal: ospi: refactor creation

Refactor the OSPI controller creation using the VersalMap structure.

Note that the connection to the PMC IOU SLCR is removed for now and will
be re-added by next commits.

Signed-off-by: Luc Michel <luc.michel@amd.com>
Reviewed-by: Francisco Iglesias <francisco.iglesias@amd.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@amd.com>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20250926070806.292065-12-luc.michel@amd.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>