xtest: add --stats applet

Adds the --stats applet to interact with the pseudo TA "stats".

Acked-by: Jerome Forissier <jerome.forissier@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
diff --git a/Android.mk b/Android.mk
index 73d1fb7..1005ded 100644
--- a/Android.mk
+++ b/Android.mk
@@ -49,6 +49,7 @@
 	regression_8000.c \
 	regression_8100.c \
 	sha_perf.c \
+	stats.c \
 	xtest_helpers.c \
 	xtest_main.c \
 	xtest_test.c