build_helper_configs: Add "debug_regr" config

Copy of existing "debug" config, with regression tests enabled. Helpful
e.g. to test code coverage.

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Change-Id: I95aa08376cae1bdfa06e4dcff1632d81017f7a5e
diff --git a/build_helper/build_helper_configs.py b/build_helper/build_helper_configs.py
index 6cbadd1..f6fce86 100755
--- a/build_helper/build_helper_configs.py
+++ b/build_helper/build_helper_configs.py
@@ -1245,7 +1245,8 @@
                   "invalid": _common_tfm_invalid_configs + []
                   }
 
-# Configuration used in testing
+# Configurations used in testing
+
 config_debug = {"seed_params": {
                 "tfm_platform":     ["arm/mps2/an521"],
                 "compiler":         ["GCC_7_3_1"],
@@ -1265,6 +1266,11 @@
                 "invalid": _common_tfm_invalid_configs + []
                 }
 
+
+config_debug_regr = config_debug.copy()
+config_debug_regr["test_regression"] = [True]
+
+
 config_debug_PSA_API = {"seed_params": {
                 "tfm_platform":     ["arm/mps2/an521"],
                 "compiler":         ["ARMCLANG_6_13"],
@@ -1601,6 +1607,7 @@
                     "ipc": config_IPC,
                     "doxygen": config_doxygen,
                     "debug": config_debug,
+                    "debug_regr": config_debug_regr,
                     "debug_PSA_API": config_debug_PSA_API,
                     "debug_PSA_API_nolib": config_debug_PSA_API_nolib,
                     "release": config_release,