log: syslog driver

Provide a log driver that broadcasts RFC 3164 messages to syslog servers.
rsyslog is one implementation of such a server.

The messages are sent to the local broadcast address 255.255.255.255 on
port 514.

The environment variable log_hostname can be used to provide the HOSTNAME
field for the messages. The optional TIMESTAMP field of RFC 3164 is not
provided.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index d8d420f..0bafe5c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -654,7 +654,7 @@
 M:	Simon Glass <sjg@chromium.org>
 S:	Maintained
 T:	git https://gitlab.denx.de/u-boot/u-boot.git
-F:	common/log.c
+F:	common/log*
 F:	cmd/log.c
 F:	test/log/log_test.c
 F:	test/py/tests/test_log.py