build: add correct libsystemd dependency

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I068de971f7e57a86493d5d0d0be9fc944ec1ef2f
diff --git a/Makefile.am b/Makefile.am
index 9e839a9..14cd3f7 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -7,9 +7,11 @@
 				sysfs.cpp
 
 phosphor_ledcontroller_LDFLAGS = $(SDBUSPLUS_LIBS) \
+                                 $(SYSTEMD_LIBS) \
                                  $(PHOSPHOR_DBUS_INTERFACES_LIBS) \
 				 -lstdc++fs
 phosphor_ledcontroller_CFLAGS =  $(SDBUSPLUS_CFLAGS) \
+                                 $(SYSTEMD_CFLAGS) \
                                  $(PHOSPHOR_DBUS_INTERFACES_CFLAGS)
 
 if AUTOCONF_CODE_COVERAGE_2019_01_06