tfm: Fix undefined reference to 'end' when disabling secure output

Fix undefined reference to 'end' when disabling secure output from the
TF-M image.

When secure output is disabled the printf function is not overriden
in TF-M and the libc variant has references to heap functions.
Make sure that the printf function is overriden for this case also and
drop the output message.

NCSDK-22818

Signed-off-by: Joakim Andersson <[email protected]>

Author: joerchan

modules/tfm/tfm/boards/CMakeLists.txt

@@ -65,6 +65,11 @@ if (NOT ${PLATFORM_DEFAULT_PROVISIONING})
     )
 endif()
 
+target_sources(tfm_sprt
+    PRIVATE
+        $<$<NOT:$<BOOL:${TFM_SP_LOG_RAW_ENABLED}>>:${CMAKE_CURRENT_SOURCE_DIR}/common/dummy_tfm_sp_log_raw.c>
+)
+
 # Disabling UART stdout not supported in NS Image, which is always built even when not needed.
 target_sources(platform_ns
   PRIVATE

modules/tfm/tfm/boards/common/dummy_tfm_sp_log_raw.c

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2022 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include <stdarg.h>
+#include <stddef.h>
+
+/* This function is here in case any references to printf has been accidentally
+ * left in the code. This will then mute this printfs from pulling in the real
+ * printf instead of the function defined in tfm_sp_log_raw.c when this file
+ * is not part of the build.
+ */
+int printf(const char *fmt, ...)
+{
+        return 0;
+}