Silence org.apache.sshd.common debug messages

Messages like:

  2009-01-28 13:21:56,884::DEBUG: org.apache.sshd.common.channel.Window - Increase server local window by 262263 up to 2088960

aren't that interesting to the server administrator.

Bug: GERRIT-52
Signed-off-by: Shawn O. Pearce <sop@google.com>
diff --git a/appjar/src/main/java/log4j.properties b/appjar/src/main/java/log4j.properties
index 9cfa9ec..b156415 100644
--- a/appjar/src/main/java/log4j.properties
+++ b/appjar/src/main/java/log4j.properties
@@ -6,5 +6,5 @@
 
 # Silence non-critical messages from MINA SSHD.
 #
-log4j.logger.org.apache.sshd.common.util.SecurityUtils=WARN
+log4j.logger.org.apache.sshd.common=WARN
 log4j.logger.org.apache.sshd.server=WARN