tests: Add LTO tests variants with LTO_SINGLE_THREADED

Add variants of existing tests to cover this new Kconfig option.

Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>

Author: carlescufi

tests/kernel/common/testcase.yaml

@@ -89,3 +89,17 @@ tests:
     integration_platforms:
       - qemu_x86
       - mps2/an385
+  kernel.common.lto.singlethreaded:
+    platform_key:
+      - arch
+    # CONFIG_CODE_DATA_RELOCATION causes a build error (issue #69730)
+    filter: CONFIG_ISR_TABLES_LOCAL_DECLARATION_SUPPORTED and not CONFIG_CODE_DATA_RELOCATION
+    tags: lto
+    extra_configs:
+      - CONFIG_TEST_USERSPACE=n
+      - CONFIG_ISR_TABLES_LOCAL_DECLARATION=y
+      - CONFIG_LTO=y
+      - CONFIG_LTO_SINGLE_THREADED=y
+    integration_platforms:
+      - qemu_x86
+      - mps2/an385

tests/misc/test_build/testcase.yaml

@@ -36,6 +36,15 @@ tests:
       - CONFIG_ISR_TABLES_LOCAL_DECLARATION=y
       - CONFIG_LTO=y
       - CONFIG_PICOLIBC_USE_MODULE=y
+  buildsystem.lto.st.picolibc_module:
+    build_only: true
+    platform_allow:
+      - nucleo_f746zg
+    extra_configs:
+      - CONFIG_ISR_TABLES_LOCAL_DECLARATION=y
+      - CONFIG_LTO=y
+      - CONFIG_LTO_SINGLE_THREADED=y
+      - CONFIG_PICOLIBC_USE_MODULE=y
   buildsystem.arm.null_pointer_exception_detection_dwt:
     build_only: true
     platform_allow: