Build: re-enable FLIH tests

This reverts commit f2623acf8ae6230605b541f475b82b203532fc4c.

The issue on FLIH tests has been fixed. So re-enable FLIH tests in CI.

Signed-off-by: Xinyu Zhang <xinyu.zhang@arm.com>
Change-Id: If73dd565a66a6ba484c0144a4c26895e4ed282e6
diff --git a/build_helper/build_helper_configs.py b/build_helper/build_helper_configs.py
index 5eb20ed..161a782 100755
--- a/build_helper/build_helper_configs.py
+++ b/build_helper/build_helper_configs.py
@@ -49,7 +49,7 @@
         "-DTFM_PLATFORM=%(tfm_platform)s " + \
         "-DTFM_TOOLCHAIN_FILE=%(codebase_root_dir)s/%(compiler)s " + \
         "-DTFM_ISOLATION_LEVEL=%(isolation_level)s " + \
-        "-DTEST_NS=%(test_regression)s -DTEST_S=%(test_regression)s -DTEST_NS_FLIH_IRQ=OFF " + \
+        "-DTEST_NS=%(test_regression)s -DTEST_S=%(test_regression)s " + \
         "-DTEST_BL2=%(test_regression)s " + \
         "-DCMAKE_BUILD_TYPE=%(cmake_build_type)s " + \
         "-DTEST_PSA_API=%(test_psa_api)s " + \