Suppress "invalid facility message" when using stderr only

This annoying/irrelevant message was probably an oversight to begin
with.

Commit message kibitzed by Daniel Farina <[email protected]>

wal_e/log_help.py

@@ -80,6 +80,10 @@ def terrible_log_output(s):
     valid_facility = False
     if 'syslog' in log_destinations:
         facility, valid_facility = get_syslog_facility()
+
+        if not valid_facility:
+            terrible_log_output('invalid syslog facility level specified')
+
         try:
             # Add syslog output.
             HANDLERS.append(handlers.SysLogHandler(syslog_address,
@@ -103,10 +107,6 @@ def terrible_log_output(s):
     # Default to INFO level logging.
     set_level(kwargs.get('level', logging.INFO))
 
-    if not valid_facility:
-        WalELogger(__name__).warning(
-            msg='invalid syslog facility level specified')
-
 
 def get_log_destinations():
     """Parse env string"""