pp_test: Add isolation level 1 and IPC model config

The default SPM backend model on isolation level 1 is SFN, thus
cross call is not covered under pp_test.

Signed-off-by: Jianliang Shen <jianliang.shen@arm.com>
Change-Id: Ie6d620b0979682e690cc474eb112ffda5d897852
diff --git a/build_helper/build_helper_configs.py b/build_helper/build_helper_configs.py
index 44643cf..f567ff0 100755
--- a/build_helper/build_helper_configs.py
+++ b/build_helper/build_helper_configs.py
@@ -214,6 +214,9 @@
                     # AN521_ARMCLANG_1_RegBL2_RegS_RegNS_Debug_BL2
                     ("arm/mps2/an521", "ARMCLANG_6_13", "1",
                      "RegBL2, RegS, RegNS", "OFF", "Debug", True, "", ""),
+                    # AN521_ARMCLANG_1_RegBL2_RegS_RegNS_Debug_BL2_IPC
+                    ("arm/mps2/an521", "ARMCLANG_6_13", "1",
+                     "RegBL2, RegS, RegNS", "OFF", "Debug", True, "", "IPC"),
                     # AN521_ARMCLANG_2_RegBL2_RegS_RegNS_Release_BL2
                     ("arm/mps2/an521", "ARMCLANG_6_13", "2",
                      "RegBL2, RegS, RegNS", "OFF", "Release", True, "", ""),