Fault rather than looping on secondary abort, so tests fail quickly.

Before an assertion failure in a secondary would result in the test timing
out. Now it will fail immediately, as the fault returns control to the
primary.

Change-Id: I58e77c3f881deaa3d0205a3ead5b2d1b6660b124
diff --git a/test/hftest/hftest_service.c b/test/hftest/hftest_service.c
index 455b86a..1278617 100644
--- a/test/hftest/hftest_service.c
+++ b/test/hftest/hftest_service.c
@@ -68,11 +68,11 @@
 noreturn void abort(void)
 {
 	HFTEST_LOG("Service contained failures.");
+	/* Cause a fault, as a secondary can't power down the machine. */
+	*((volatile uint8_t *)1) = 1;
+
+	/* This should never be reached, but to make the compiler happy... */
 	for (;;) {
-		/*
-		 * Hang if the service aborts as a secondary can't power down
-		 * the machine.
-		 */
 	}
 }