tftf*: Unhandled exception during tests is a test fail-fast

Similar to other fail-fast strings added recently, to prevent failing jobs
to hang until timeout.

Seen at https://tf.validation.linaro.org/scheduler/job/1677111

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Change-Id: I6a9e985f47ad4252b58a74d3b6c8e7022b6fcdcc
diff --git a/expect-lava/tftf-aarch32.exp b/expect-lava/tftf-aarch32.exp
index 6279f19..df0b752 100644
--- a/expect-lava/tftf-aarch32.exp
+++ b/expect-lava/tftf-aarch32.exp
@@ -16,7 +16,8 @@
 expect_string+=("i;${prompt}")
 
 prompt='Tests Failed  : 0'
-expect_string+=("i;${prompt}")
+failures='Unhandled exception on '
+expect_string+=("i;${prompt};;${failures}")
 
 prompt='Exiting tests.'
 failures='Tests Passed  : 0'
diff --git a/expect-lava/tftf-non-primary.exp b/expect-lava/tftf-non-primary.exp
index eb8ad46..521b43f 100644
--- a/expect-lava/tftf-non-primary.exp
+++ b/expect-lava/tftf-non-primary.exp
@@ -13,7 +13,8 @@
 expect_string+=("i;${prompt}")
 
 prompt='Tests Failed  : 0'
-expect_string+=("i;${prompt}")
+failures='Unhandled exception on '
+expect_string+=("i;${prompt};;${failures}")
 
 prompt='Exiting tests.'
 failures='Tests Passed  : 0'
diff --git a/expect-lava/tftf.exp b/expect-lava/tftf.exp
index 4b132cd..f599192 100644
--- a/expect-lava/tftf.exp
+++ b/expect-lava/tftf.exp
@@ -16,7 +16,8 @@
 expect_string+=("i;${prompt}")
 
 prompt='Tests Failed  : 0'
-expect_string+=("i;${prompt}")
+failures='Unhandled exception on '
+expect_string+=("i;${prompt};;${failures}")
 
 prompt='Exiting tests.'
 failures='Tests Passed  : 0'