Test: Output EOT (\x04) char at the end of test

When running in FVP (Fixed Virtual Platform), that will allow to terminate
running using options like fvp_mps2.UART0.shutdown_on_eot or
fvp_mps2.UART0.shutdown_tag. This is important in CI systems, etc.

A similar convention is used in TF-A tests.

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Change-Id: I06eeef7692611c6f8cdb1aedce0e5aad440349b5
diff --git a/app/tfm_integ_test.c b/app/tfm_integ_test.c
index 3f69969..0430837 100644
--- a/app/tfm_integ_test.c
+++ b/app/tfm_integ_test.c
@@ -6,6 +6,7 @@
  */
 
 #include "tfm_integ_test.h"
+#include "tfm_log.h"
 
 #ifdef TEST_FRAMEWORK_NS
 #include "test_framework_integ_test.h"
@@ -38,6 +39,8 @@
 #ifdef TEST_FRAMEWORK_NS
     tfm_non_secure_client_run_tests();
 #endif
+    /* Output EOT char for test environments like FVP. */
+    LOG_MSG("\x04");
     /* End of test */
     for (;;) {
     }