boards: arm: mps3: fix intermittent ci failures

Fixes #90654

Signed-off-by: Sudan Landge <sudan.landge@arm.com>

Author: wearyzen

boards/arm/mps3/mps3_corstone300_fvp.yaml

@@ -17,6 +17,7 @@ supported:
   - gpio
 testing:
   default: true
+  timeout_multiplier: 4
   ignore_tags:
     - bluetooth
     - net

boards/arm/mps3/mps3_corstone300_fvp_ns.yaml

@@ -1,4 +1,4 @@
-# Copyright 2024 Arm Limited and/or its affiliates <open-source-office@arm.com>
+# Copyright 2024-2025 Arm Limited and/or its affiliates <open-source-office@arm.com>
 # SPDX-License-Identifier: Apache-2.0
 
 identifier: mps3/corstone300/fvp/ns
@@ -12,5 +12,6 @@ toolchain:
   - zephyr
 testing:
   default: true
+  timeout_multiplier: 4
   only_tags:
     - trusted-firmware-m

boards/arm/mps3/mps3_corstone310_fvp.yaml

@@ -17,6 +17,7 @@ supported:
   - gpio
 testing:
   default: true
+  timeout_multiplier: 4
   ignore_tags:
     - drivers
     - bluetooth

boards/arm/mps3/mps3_corstone310_fvp_ns.yaml

@@ -1,4 +1,4 @@
-# Copyright 2024 Arm Limited and/or its affiliates <open-source-office@arm.com>
+# Copyright 2024-2025 Arm Limited and/or its affiliates <open-source-office@arm.com>
 # SPDX-License-Identifier: Apache-2.0
 
 identifier: mps3/corstone310/fvp/ns
@@ -12,5 +12,6 @@ toolchain:
   - zephyr
 testing:
   default: true
+  timeout_multiplier: 4
   only_tags:
     - trusted-firmware-m