rsyslog: move systemd support to rsyslog-systemd
rsyslog: move systemd support to rsyslog-systemd

This makes the package consistent with others supporting systemd and
also cleans up the recipe using the systemd.bbclass.

Signed-off-by: Otavio Salvador <1d31b11c1b92bf5d043d36edfe7174db39a6b891@ossystems.com.br>

WindRiver-OpenSourceLabs/meta-oe-subset,WindRiver-OpenSourceLabs/meta-oe-subset