build: Add missing inclusion of phosphor-logging

Phosphor-logging is picked up by the configure_ac.
Include it in the Makefile such that it's available
as defined by the pkgconfig.

Change-Id: I173fa376ab3419155267ab08350d7a7ad2e1a0f0
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/Makefile.am b/Makefile.am
index 0aadf6c..205c708 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -19,10 +19,13 @@
 phosphor_timemanager_LDADD = libtimemanager.la
 
 generic_cxx_flags = $(PHOSPHOR_DBUS_INTERFACES_CFLAGS) \
-                    $(SDBUSPLUS_CFLAGS) -flto
+                    $(SDBUSPLUS_CFLAGS) \
+                    $(PHOSPHOR_LOGGING_CFLAGS) \
+                    -flto
 
 generic_ld_flags = $(PHOSPHOR_DBUS_INTERFACES_LIBS) \
-                   $(SDBUSPLUS_LIBS)
+                   $(SDBUSPLUS_LIBS) \
+                   $(PHOSPHOR_LOGGING_LIBS)
 
 libtimemanager_la_CXXFLAGS = $(generic_cxx_flags)
 libtimemanager_la_LIBADD = $(generic_ld_flags)