busybox: enable shared memory logging for systemd

busybox: enable shared memory logging for systemd

The default command-line options for launching busybox's syslogd are
"-C" if using sysvinit; but because we use /etc/default/busybox-syslog
when using systemd which the sysvinit initscript doesn't use, and no
/etc/default/busybox-syslog is installed by default in OE-Core, the
default arguments with systemd were no arguments at all with OE-Core
alone. Effectively merge in the bbappend from meta-oe that adds a
default file in order to set the default options to "-C" for systemd as
well.

(From OE-Core rev: a23aa8e7467cf2b7f4e8ff85a3aa841ff6b508e5)

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>