boards: mps2_an521_ns: Remove simulation capability

This board requires TF-M which is not supported by default in the
current Zephyr release. Just remove the simulation capability to
avoid CI failures.

See: #54084

Signed-off-by: Flavio Ceolin <[email protected]>

Author: Flavio Ceolin

boards/arm/mps2_an521/mps2_an521_ns.yaml

@@ -4,7 +4,10 @@ type: mcu
 arch: arm
 ram: 4096
 flash: 4096
-simulation: qemu
+  # TFM is not supported by default in the Zephyr LTS release.
+  # Excluding this board's simulator to avoid CI failures.
+  #
+  #simulation: qemu
 toolchain:
   - gnuarmemb
   - zephyr