Add Gtest to test watchdog

Change-Id: Ia0268b6b18999b6dd6cfd26bcadcff25734306f0
Signed-off-by: Vishwanatha Subbanna <vishwa@linux.vnet.ibm.com>
diff --git a/Makefile.am b/Makefile.am
index cd58d99..2e9a4f1 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -18,3 +18,5 @@
                              ${PHOSPHOR_LOGGING_CFLAGS} \
                              ${SDBUSPLUS_CFLAGS} \
                              ${PHOSPHOR_DBUS_INTERFACES_CFLAGS}
+
+SUBDIRS = test