Build: Add group for IPC backend

Signed-off-by: Xinyu Zhang <xinyu.zhang@arm.com>
Change-Id: I10f64fcce7d3cc6a79da46b3544e6c633a3d0730
diff --git a/build_helper/build_helper_config_maps.py b/build_helper/build_helper_config_maps.py
index 61a94df..984e2c6 100644
--- a/build_helper/build_helper_config_maps.py
+++ b/build_helper/build_helper_config_maps.py
@@ -68,6 +68,8 @@
     "LZOFF"        : "-DCONFIG_TFM_LAZY_STACKING=OFF ",
     # Partiton
     "PSOFF"        : "-DTFM_PARTITION_PROTECTED_STORAGE=OFF ",
+    # IPC
+    "IPC"          : "-DCONFIG_TFM_SPM_BACKEND=IPC ",
     # CC Driver
     "CC_DRIVER_PSA": "-DCC312_LEGACY_DRIVER_API_ENABLED=OFF ",
     # ST support