libsyslog: drop extra leading space in message

When logging to a file we want a space to separate proc[pid]: from the
message, but for regular logging local/remote we don't want to inject
an extra space.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

src/syslog.c

@@ -322,6 +322,7 @@ vsyslogp_r(int pri, struct syslog_data *data, const char *msgid,
 			iov[iovcnt].iov_len = prlen;
 			iovcnt++;
 		}
+		prlen--; /* drop extra space for regular log messages */
 		DEC();
 		goto output;
 	}