Clarify why the AST_LOG_* macros exist next to the LOG_* macros.

(issue ASTERISK-17973)
........

Merged revisions 345923 from http://svn.asterisk.org/svn/asterisk/branches/1.8


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/10@345924 65c4cc65-6c06-0410-ace0-fbb531ad65f3

include/asterisk/logger.h

@@ -107,8 +107,8 @@ void ast_console_toggle_loglevel(int fd, int level, int state);
 
 /* Note: The AST_LOG_* macros below are the same as
  * the LOG_* macros and are intended to eventually replace
- * the LOG_* macros to avoid name collisions as has been
- * seen in app_voicemail. However, please do NOT remove
+ * the LOG_* macros to avoid name collisions with the syslog(3)
+ * log levels. However, please do NOT remove
  * the LOG_* macros from the source since these may be still
  * needed for third-party modules
  */