soc: rp2350: Exclude image definition block from MCUboot application images

[psimonte]

Application images intended for MCUboot should not include the .image_def section. This change adjusts the linker configuration to only include the image definition block when building standalone images.

Otherwise the Build will fail when setting CONFIG_BOOTLOADER_MCUBOOT=y

[github-actions]

Hello @psimonte, and thank you very much for your first pull request to the Zephyr project!
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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[soburi]

#86294

This PR has been merged ahead of time and may contain the change you need, so please check it out.

[github-actions]

This pull request has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this pull request will automatically be closed in 14 days. Note, that you can always re-open a closed pull request at any time.

[dsseng]

Please consider taking a look as #91200 has now landed, and it reorders some of the configs in a way that could benefit your needs

[github-actions]

This pull request has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this pull request will automatically be closed in 14 days. Note, that you can always re-open a closed pull request at any time.