unit-test: Test interfaces added function

Tested:
- processing.cpp at 94% coverage
- Verified QEMU booted to standby and mapper command line worked
- Verified hardware CI (witherspoon) passed with this patch series

Change-Id: I73e5feb3495ed0aa974acd521fefd8d0193fc1b3
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/src/test/Makefile.am.include b/src/test/Makefile.am.include
index 394c610..0ca04b8 100644
--- a/src/test/Makefile.am.include
+++ b/src/test/Makefile.am.include
@@ -10,8 +10,12 @@
 src_test_name_change_SOURCES = %reldir%/name_change.cpp \
 		src/associations.cpp src/processing.cpp
 
+src_test_interfaces_added_SOURCES = %reldir%/interfaces_added.cpp \
+		src/associations.cpp src/processing.cpp
+
 check_PROGRAMS += \
 	%reldir%/well_known \
 	%reldir%/need_to_introspect \
 	%reldir%/associations \
-	%reldir%/name_change
+	%reldir%/name_change \
+	%reldir%/interfaces_added