enable unit-tests: enable for SensorManager

Enabled unit-tests in general for the project, and more
specifically started with a benign construction test for
the SensorManager object.

Tested: Verified continues to build and link, and unit-test
passes.
Tested: Ran on quanta-q71l board and it behaved as expected.

Change-Id: I4ad9a0c57efd0b9ccc37d26faa0cc1b82026b8d7
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/test/Makefile.am b/test/Makefile.am
index ea93a96..738ab91 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -12,5 +12,9 @@
 	$(PHOSPHOR_DBUS_INTERFACES_LIBS)
 
 # Run all 'check' test programs
-check_PROGRAMS =
+check_PROGRAMS = sensor_manager_unittest
 TESTS = $(check_PROGRAMS)
+
+# Until libconfig is mocked out or replaced, include it.
+sensor_manager_unittest_SOURCES = sensor_manager_unittest.cpp
+sensor_manager_unittest_LDADD = $(top_builddir)/sensors/manager.o