systemd: Reload configuration on package install

When a systemd service file has changed it is required to reload
systemd's configuration. Otherwise changes to a service file will not be
picked up during package upgrade.

(From OE-Core rev: 94efe6d1d7893e241bcf98eff80ac8d8fbf2e885)

Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/systemd.bbclass

@@ -29,6 +29,10 @@ if [ -n "$D" ]; then
 fi
 
 if type systemctl >/dev/null 2>/dev/null; then
+	if [ -z "$D" ]; then
+		systemctl daemon-reload
+	fi
+
 	systemctl $OPTS ${SYSTEMD_AUTO_ENABLE} ${SYSTEMD_SERVICE}
 
 	if [ -z "$D" -a "${SYSTEMD_AUTO_ENABLE}" = "enable" ]; then