Add API to retrieve settings

Add API to retrieve all settings objects of interest to the time
manager.

Change-Id: I3d121c08d0156cf481a3468e6c7ca9b71f53d666
Signed-off-by: Deepak Kodihalli <dkodihal@in.ibm.com>
diff --git a/configure.ac b/configure.ac
index 2769644..fc0da82 100644
--- a/configure.ac
+++ b/configure.ac
@@ -16,6 +16,12 @@
 # Checks for libraries.
 AC_CHECK_LIB([mapper], [mapper_get_service], ,[AC_MSG_ERROR([Could not find libmapper...openbmc/phosphor-objmgr package required])])
 PKG_CHECK_MODULES([SYSTEMD], [libsystemd >= 221])
+PKG_CHECK_MODULES([PHOSPHOR_DBUS_INTERFACES], [phosphor-dbus-interfaces],,\
+    AC_MSG_ERROR(["Requires phosphor-dbus-interfaces package."]))
+PKG_CHECK_MODULES([SDBUSPLUS], [sdbusplus],,
+    AC_MSG_ERROR(["Requires sdbusplus package."]))
+PKG_CHECK_MODULES([PHOSPHOR_LOGGING], [phosphor-logging],,\
+    AC_MSG_ERROR(["Requires phosphor-logging package."]))
 
 # Checks for header files.
 AC_CHECK_HEADER(systemd/sd-bus.h, ,[AC_MSG_ERROR([Could not find systemd/sd-bus.h...systemd developement package required])])